DETAILED REVIEW OF THE 19 FEB 2012 WXRISK.COM FORECAST

Posted by wxrisk | GENERAL,WINTER 2011-12 | Monday 27 February 2012 10:12 pm

2000  EST  27  FEB  2012….. STARDATE   201202.27

 

Exactly one week ago  — FEB 19– eastern Kentucky the southern half a West Virginia and Virginia experienced a significant snowstorm.  I have had a week now to think about   this event and to compile all of my forecasts… statements and present a thorough review.  Thus this  web page entry.

In addition I will explain why I argued so strongly that this was going to be a KY  WVA VA  snowstorm and that the system had little chance of turning up the coast into the big cities of the northeast.  As  we go  through this analysis  I will stress  several key points.

  1.  The  pattern  strongly favored  this Low tracking ENE  off the NC coast and not coming  up the coast.   Unfortunately   many Meteorologists  and weather Hobbyists  along the  East coast  were   ignorant   of this and blindly  clung to the   old  saying
    ” the north trend “. 
  2.  The GFS Model  performance sucked moose. The Model performance was appallingly  bad   in the period from  day 10/ FEB 10  to  Day2/FEB 17 with frequent  wild swings  from  solution to solution.  
  3.  The close adherence of this seriously  flawed Model by   weather  hobbyist and professional meteorologist caused unnecessary Hedging and   uncertainty in the forecast.

 

The first statement was issued by me based upon the Day 10 12z European model February 10 run….  which showed a significant Low pressure area along the just off the southeast coast of North Carolina.  It turns out that the day 10 European model from FEB 10 was amazingly accurate and as close to a direct hit with respect to the actual surface   on February 19   for a  ten day forecast as  you have.  Of course the   FEB 10 European model   was off by one day but still  the  day 10 European  model  depiction  was pretty darn good.

FRIDAY  FEB 10  235 PM  I  posted    this:

* ALERT DAY 10 EUROPEAN MODEL HAS MAJOR EAST COAST SNOWSTORM … even for most of NC and all of MD and VA on  FEB 20

Of course several  times this winter we seen false alerts from weather models especially  at Day 8  Day 10  and Day 12.  However in this  case something was different with respect to the large scale or synoptic pattern.  The PRIMARY    reason WHY I believe this event had a better chance to become a reality  and a significant  event  … even at Day 10…  was the collapse  that was  forecasted by all the models of the super intense and large Polar  Vortex   (PV) over Eastern Canada.

I have said this many times before and I am sure I will say again.  The overwhelming amount of data shows that having a large powerful intense PV over eastern Canada— over Hudson’s Bay or  central or Northern Quebec / or Labrador–is an extremely negative or Hostile  synoptic  feature to development of major East Coast Winter storms.  Having the PV below 500 dm  in that geographical position is a  manifestation of the  + AO pattern.  That being  said … if  one  looks at the 500 mb maps  in  January and  early February you would  have seen a   large intense   PV  situated consistently over northern Hudson’s bay or Northern Quebec  or Baffin island.  Sometimes this feature has been as low as  474  dm and has been so large that it has  6  or  8     lines — height lines –around it.   That represents a lot of wind and  energy and becomes extremely hard to get the Polar Jet  (PJ)  to dive south and  merge or   “phase” with  the subtropical jet  (STJ)  over the Eastern CONUS.  And without the phasing…  you don’t get big winter East Coast storms.

In addition on the 10th I argued that  another key aspect to this  POSSIBLE event  happening was the cold front and significant Low pressure area tracking through the Great Lakes and February 17.  In order for this possible winter storm scenario to develop  the Great Lakes   Low had to move into southeastern Canada and become a  50 /50 Low.  This in turn would force the cold air south  into the Northeast   US and prevent the next system and tracking up into the Ohio Valley.

The    12z  FEB 10 european  had some partial support the next morning   from the 6z   GFS but  the model  truncation  after day 8/192 hour  clearly  caused the  flawed  GFS Model  to “lose ” the southern  system (the short  wave)  at the 500 MB.

The  12z  FEB 11  operational  European  model had the  southeast Low  but it was further south. The 12z  euro  ensemble  had the Low 200 miles further North  and this trend continued  with the 0z  FEB 12  run of the Operational European… and I posted   this  on the Facebook  (FB) page at 0155 hrs  12FEB

*** ALERT *** ABOUT FEB 19-20 THREAT ****  
The  NEW 0Z — early Sunday AM –   run of   the  ECMWF ( the european) shows a  CLASSIC VA -NC -MD SNOWSTORM  … but only  IF one looks at UPPER AIR maps .   But the surface map does NOT look all that good.   At 500mb  on day 8 – 7PM SAT FEB 18 the 0z euro has closed 500 Low centered over central ILL -IND…. the surface Low for  some reason is waaaay to the south which makes NO sense . The Model has the surface Low on the SC coast which is a tad  further North than the 12z Saturday run. BY the Morning of FEB 19 the closed 500 low is right over southern VA … and there is some snow falling  over central and eastern VA…. but again the Surface Low is waaaaaaay to the east which makes NO sense.

On the   other hand   the 0z  GFS   took the Low  into the Great Lakes  and  developed a   strong  SE  ridge.

However the 12z GFS  FEB 12  run  showed  a Major change or     “flip flop”  in that  the Model  took the Low  from MI  to the  GA coast and showed the   southern energy  — the short  wave–  weakening   rapidly as  it  propagated  east along  the  Gulf coast.

The 12z  Euro  run on 12 FEB  remained   very consistent. The model  detected   2   pieces of energy — 2  short waves -  over  TX and KS –  that   merged  or  Phased into  a  stronger  southern short wave  that developed a  Negative   tilt.  This in turn argued that the  surface Low  should be closer to the coast  than what the  Model  was depicting with its surface map for  FEB 19.

A SIGNIFICANT  development  occurred on the  0z  FEB 13 Model runs when the CMC or Canadian  model which had been showing no  development of the southern shortwave for the last several model runs…  turned it towards the European solution by developing a significant area of Low pressure along the Southeast US coast that bought significant snow into the southern half of Virginia.  Such a development of course began speculation about the new north trend as it almost always does but as we will see in this case that was not to be for number of different reasons.   On MONDAY    FEB 13    at 0121  hrs  I posted this …

‎0Z CMC MAPS FOR ALL TO SEE.. SIGNIFICANT SNOWFALL for southern VA standards NOT for say NYC or PHL or BOS standards into southern 25% of VA. This is BIG leap in what THIS Model was showing when compared to earlier runs… 

The trend continued with the 0z   13 FEB  run of the European model which showed it even bigger and more developed southeast US  coastal Low   tracking the low over or close to Cape  Hatteras. However the model began to experience problems with the northern and the precipitation shield.

Later that day  the  the operational run   of the 12z FEB  13 run of    GFS   Model came out with a dramatically different solution which caused a significant reaction with some of the more poorly informed meteorologists.  The GFS showed a major jump northward in its position of the southeast low so that it bought significant snow into the big cities of the northeast. Upon seeing this run I posted the following on the FB  page

* COMMENTS ON 12Z MONDAY 13 FEB  GFS run — REGARDING FEB 19-20 ** Ignore this run of the GFS ..it has huge error in it that Just forces the model to go off the reservation into idiot land.

This was followed by the assessment from  HPC/ NWS the declared the  12z 13 FEB  operational GFS to be seriously flawed bcause of corrupted data the getting into the model .

Of course that drew a very strong reaction from several sources both from whether hobbyists and from professional meteorologist who should have known better.  The statement from HPC was pretty strong and I don’t see how anybody could have possibly ignored their argument.

Leading the charge that the GFS solution was correct after all was of course  Joe Bastardi.  He made the argument that this  dropping  the operational GFS and its north trend was the same sort of mistake that  HPC made   with regard to the East Coast historic snowstorm   25-26  DEC  2010.  If you recall the  particulars  of that event … it brought 10 to 20 inches of snow from   eastern NC through  Norfolk across the lower Maryland eastern shore into the big cities of Philadelphia New Jersey and New York City and then into Southern New England.

Bastardi argument was of course absurd and had  little basis in reality but he counts on weather  hobbyists  not having a firm grasp of what the actual facts were in a particular situation.  The truth is that in the days leading up to the  25-26 DEC  2010 historic snowstorm   ALL of the models had   shown the same solution for several days.  This was not a case of one model showing ABC  while another model showed  XYZ   and another  showed  HIJ.  But more importantly on the day before the actual   25 DEC 2010   Major  East Coast Snowstorm …   all the model data   — the European …  the Canadian ….the British  AND  the GFS  ….and ALL of  the short range models for that matter as well — all took the potential coastal snowstorm   way out to sea .  It was  NOT  the case of a   ONE  model coming up with a bizarre solution and being dropped by   HPC.

In addition his analogy also fails because just as all the models both the global and shore range models  suddenly took the coastal storm out to sea on  the December 24 model  runs…  that Night  on Christmas Eve …ALL  of the models  suddenly  reversed course and bought and be major snowstorm for the immediate  coastal areas from Virginia to Boston.

Never let facts get in the way of good   Bullshit.

Fortunately even while the debate regarding the  obviously flawed  12z GFS  Model was raging on midday on the 13th of February   the 12z  Ukmet  came out and showed a  Major   se US Low tracking over Cape Hatteras and moving out to sea bringing a significant snowstorm to much of western NC …VA … and   southern Maryland.

1239PM  FEB 13  I  made this  post on  the FB page

**ALERT *** ALERT *** 12Z UKMET GOES BOOM.. shows major east coast snowstorm FEB 19…. for entire Middle Atlantic even VA and MD into NYC LI and southern  CT.

This was followed shortly by the  12z run  of the European model which developed the southeast low a little deeper and took it further to the north ride along the South Carolina North Carolina coastal areas with the track running from Charleston to Wilmington to Cape Hatteras.   This cause me to make the following post  on the FB page.

FEB 13  132  PM     ‎*** ALERT *** ALERT ***ALERT …. this is No drill … 12Z EURO brings  in MUCH stronger  SE US Low   with HEAVY SNOW to all of central and eastern VA –over 6 inchesand much of Northern NC …. POSSIBLE ACCUMULATING SNOW late on the 18th into the 19th… WOOF WOOF BARK WOOF…  

At this Point I tried to make the argument that  the overall pattern clearly did not support a north trend and that the system was not a threat for the big cities the northeast.  Despite the strongly worded statement  from HPC and    the  fact that  the   12z  European Canadian and British models all strongly disagreed with the flawed  12z 13 FEB  GFS   run…  there continue to be a lot of desperate hope   and  the strongly worded assertions that the  12z GFS  was  somehow … that HPC   was wrong ..  had to be at least take into consideration .

However there  was  another way to of solve this dilemma as to which model solution was valid and  which one was not.  That would be to look at the historical analogs and finding similar events as well as using your brain to understand the potential scenarios that a forecast of may consider.

There are specific reasons  or    mechanisms   in the atmosphere  that  determine WHY   Low pressure areas in the winter months that  form in the Gulf     will    turn up the coast  and why some do Lows  are  forced to turn out to sea near or to the south of Cape Hatteras.  This is a science and it is not supposed to  be based on whimsical  Nonsense.    These 3   particular instances or analogs of significant snowstorms   for the lower Middle Atlantic region highlight the reasons and the mechanisms as to WHY Low pressure   along the southeast   US coast might NOT come up the coast.

However if you are unfamiliar with these events and you do not understand the significance of the players on the field especially at   500 MB then you would mis-read the Models and end at making a bad forecast period

  3  CLASSIC  LOWER MIDDLE  ATLANTIC — NC    VA  southern MD   –  SNOWSTORMS OF THE PAST.

case #1  30 JAN 1995…

This first event from 30 JAN 1995… is a very close match to the event of February 19, 2012.  This first image shows the upper air map on the 30 for January, 1995.  As you can see   there is an ULL — Upper Level Low — over the Tennessee Valley in a manner that was very similar to the event of  19 FEB 2012.  But in addition there was a  strong   PV – polar vortex-  located over Eastern Canada.  The PV in the Middle of JAN 1995 was a very intense large PV…  in a manner of very similar to what we saw in the beginning of February  2012.

 

The SURFACE Map shows   the   se US Low tracking along with just off the Southeast U.S. Coast very close to Cape Hatteras.  These
precipitation maps from   29-30 JAN  1995… and    30-31  JAN   1995 showed that significant   snow  did fall over much of Eastern Kentucky the southern portions  of West Virginia and much of southwestern and Central Virginia.  Even more significant is that in this situation just like in  19 FEB 2012……   the   heaviest snows   fell over  sw VA  and the  southern  Piedmont.

 

Notice here that he northern jet stream does  NOT  drop or phase into the southern jet stream.  Keep in mind that it is the phasing of the two jet streams between the Mississippi River and the East Coast  which is what develops the coastal Low.   If the two streams do not phase there is no MECHANISM for the   southern short  wave or Low  to come up the coast.

 CASE  #2     2-3 JAN  2002… 

This is also a very close match to the situation  of   19 FEB 2012….  Because the winter of   2001-02 has been very similar in terms of
the overall temperatures and lack of  snow  over the eastern half of  the  CONUS….  And because the winter of   2001-02  was forecasted   to be a fairly cold and stormy winter  over the eastern  CONUS  just like  2011-12.

Here is the SURFACE MAP  from  2 JAN 2002 and it seems to be a near ideal setup for  significant snowstorm into the big cities of the northeast US.

As you can see from these upper air maps JAN  1-2-3 , 2002…  there is a large and very pronounced ULL that  was centered over Iowa and Missouri on January 1.  This feature dropped into the Deep South and then rotated off the Southeast U.S. Coast by January 3.  Note again that there   was  a very deep and very intense    PV — Polar Vortex –  at  480 dm or lower located over Quebec Canada.   Also … note the very strong Pacific trough crashing into the West Coast JAN 1-2, 2002…  which again bears a striking resemblance to the  500 MB     FEB 17-19, 2012.   The analog here is striking we close to what we saw last weekend over  TN KY  NV   and VA.

Notice here that  AGAIN the northern jet stream does NOT  drop or phase into the southern jet stream.  Keep in mind that it is the phasing of the two jet streams between the Mississippi River and the East Coast which is what develops the coastal Low.  If the two
streams do not phase there is no MECHANISM for the   southern short  wave or Low  to come up the coast.

Its Just that   simple.

And by the way …there was  widespread speculation and forecast hoopla that this   Low on the se  US Coast 2 JAN 2002  was also going to turn up the coast.     And finally here is the snowfall accumulation map. In this instance   the best snows were NOT over  sw VA and the
southern Piedmont but over central and southeastern Virginia.  However the principle and the upper maps remain quite relevant and analogous  to  19 FEB 2012.

CASE # 3…   25-27 MARCH   1971…

Again the surface maps appeared to be quite favorable for significant East  Coast snowstorm.  There  is a large arctic HIGH centered over the Great Lakes covering all of the eastern CONUS and a stationary front over Florida and the gulf coast into Southern Texas with significant precipitation developing on the front.  However by 17 March 1971 the significant surface low pressure area moves off the North Carolina Coast and out to sea by passing the big cities of the Northeast.    WHY did this Low  also  ”miss”   the big cities of the  NE and why    heavy snow ONLY  fall over   eastern KY southern  WVA   northern NC and   the southern half of Virginia?

 

The 500 MB maps clearly show what happened.  In this case we have a very nice   50/50 Low centered over Newfoundland  Canada and this feature is a strong signal for potentially East Coast snowstorm .  We also have a very pronounced   -NAO as well .   And the PV is not very strong and is displaced over North Central Canada.   On 25 MARCH 1971 –  the 1st map– we see a   Upper Low Located over   KS   and the  PJ –polar Jet – is  located along or just to the north of the was Canada border and drops into New England…  while the Southern jet stream can be found running from California to Texas and Oklahoma then into the southeastern states.

On 26 MARCH 1971…  the   weak disturbance in Kansas with the Upper Low has developed significantly and is now showing in negative tilt  in the short  wave trough   — SEE BLACK  LINE–  running from   eastern KY  to the Florida panhandle.  Notice here that   AGAIN the northern jet stream does not drop or phase into the southern jet stream.   By 27 MARCH 1971   the   southern   short wave or Low has moved off the Southeast U.S. Coast into the southwest portions of the north Atlantic.

And finally the snowfall map for this event in late March 1971 showed a large area of   8  to  14″ of snow  across much southwest …  Central … South central and into Eastern Virginia.   Less than 1 inch of snow   fell in  Washington, DC and  4″ of snow  fell in   Norfolk and Virginia Beach and 7″ fell   in Williamsburg.

==============================================

Significantly  after the    12z  13 FEB operational GFS  screw up… the  12z GFS ensemble on 13FEB was much closer towards the European Canadian and British models scenarios .  Indeed the GFS  ensemble  mean was also focusing on the rapid  propagation or eastward movement of an   next incoming trough into the West Coast and towards the Rockies.

The 0z   14 FEB  Global model  runs became a significant turning point in with respect to the probability of a significant  snowstorm  for   the lower Middle Atlantic region .  The   operational GFS showed a much more organized area of low pressure coming further north along the  southeast US coast and  had  snow/ rain up to the North Carolina Virginia State line for the first time.   This was followed by the  0z  run of CMC   ( the Canadian)  which showed a major snowstorm for    the southern half of  Virginia and southern  West Virginia.    The  0z European Model   run showed perhaps the strongest surface Low  yet  with  significant snows far north as Philadelphia  and Southern New Jersey  as the 0z European Model  has the Low  coming as far North  as  37 degrees N latitude before being turned out to sea.

However the 12z   14  FEB   European model shifted the Low  to the south again.  At this Point I began to focus more heavily as to whether not there  was  any chance for phasing to occur between the two jet streams.

All winter long the pattern has featured a very strong and progressive or fast flowing Pacific jet which has not really relaxed long enough to allow for any sort of serious cold air into reasons coming south from Canada.  Very fast progress of flows are resistant to phasing between the southern and the polar jet.  I stated as such on the  FB   page

FEB 14   144PM..
I have for the last few days of favored the flatter solution as a general overall outlook be cause of this particular winter pattern. The last two winters …if you farted too loud you get a snowstorm the East Coast because the pattern allowed phasing… in fact it forced a lot of phasing or merging between the two jet streams. This result in a lot of big East Coast winter storms.

 This winter as we all know has been a very mild winter because the mean pattern or flow has been coming in from the Pacific not from Canada and the arctic regions. Thus with  THIS   possible event … I suspect that constant Pacific Jet stream energy will keep coming in from the West Coast pushing the Southern System on an easterly or eastern northeasterly track and not allowing it to turn up the coast.

The critical issue is whether or not the strong piece of energy in the southern jet stream over Alabama Mississippi mergers or phases with the northern jet stream. If it does…IF… that would pull the system further north and Northern Virginia Maryland into fairly and New Jersey would see significant snow. IF it does NOT phase then this would favor a flatter solution increase the snow threat for central and sw VA into Northern NC

ON  14  FEB  I  Posted a NOTE on the FB page   “WHERE WE STAND  ON THIS POSSIBLE THREAT   FEB 19-20”.

Withe  respect  to the debate as to whether not the operational run  of the 12z  14FEB GFS    was   valid  or  BS…  recall  this run of the GFS  has the Low coming up the coast and dropping heavy snow from DCA to BOS …  was clearly proven by the  0z  15 FEB  operational GFS which did a another flip flop and took the  Low   back to the south… along the  Southeast U.S. Coast over Cape Hatteras and out to sea.

This new flip flop by the operational GFS   model cause me to make the following commentin disgust on the  FB page…

This is why I HATE the GFS past 72 hours when it comes to East Coast winter storms. The 0z GFS model run was a massive …severe unprecedented shift…   taking  the coastal Low from the Georgia Coast … suddenly 300 Miles to the nw over ATL… From passing south and east of Cape Hatteras to passing west of Norfolk … from   showing NO precipitation of any kind north  Washington, DC
…to driving heavy snow and rain into New York City Albany and will Willaimsport PA. The fact that you may be living in the northeast big cities and the 0Z GFS is the picture perfect and one that you want to see for your location does it mean that the solution is a viable.

 The proof ? …all the OTHER weather models… ALL OF THEM…. did not show ANY significant change in their track or forecast and the updated 6z GFS has gone back to the southeast U.S. coastal solution.

At this point in my statements to   my  clients …I again stated that for Central Virginia and the Richmond metro area this was probably going to be a rain event for at least a portion of the  event  but I could not categorically rule out the threat of snow if the trend for colder  temperatures continued.  And for southwest Virginia up through the Shenandoah this look like a pretty significant snowstorm .   One  of these statements was read  on air  during the morning news show on WRVA1140 AM by Jimmy Barrett.  This prompted one of the on air meteorologists  in the Richmond metro area   to comment that   ”despite  some rumors of snow you may have heard about for Sunday the precipitation will be all rain” 

The  0z  15 FEB    run of the GFS…  Amazingly enough had a another massive model flip flop and reversal…  and now took the  southeast coastal Low  well  inland of New York City and Philly which of course  forced the model  to produce widespread significant rain.   ON the FB page  I Posted the following

FEB 15   117AM  ….    ** ALERT **8 ALERT ** IGNORE THE 12Z GFS RUN … AGAIN ** its way inland andhas rain into NYC….  c onsider   the  GFS  last run 4 runs…   12z TUES flat Low moves off NC coast out to sea…  18z TUESDAY a tad further North… 0z WAY NORTH low tracks over ATL then west of Norfolk…  6z Flat wave off the NC coast …12z  way inland and north!.

After seeing the 12Z   runs of the European …British and ….Canadian models  I    finally committed to this publicly on the FB  page  at 126pm  15   FEB

GOOD SIZE SNOWSTORM LOOKING MORE and MORE LIKELY NORTHERN VA … NW VA Northern half of SHENANDOAH VALLEY MD DE   south NJ

This commitment   to forecasting a snowstorm for the lower Middle Atlantic    was rewarded by it more changes in some of the models late on the   15th of FEB… the 0z   16   FEB Model  runs.  As I have said  many …many times… the  operational GFS is a awful model when itcomes to forecasting East Coast winter storms.   It has a lot of trouble handling Southern  short waves…   it has a lot of trouble  Phasing    the  2  jet streams just to name a few.  But once you move within  84   to 72 hours of the event   the GFS was a much better model.

Sure enough  at exactly 84 hours before the start of the event on12z 19 FEB….  the  new   0z  15 FEB    GFS Model showed a dramatic turn towards the European solution.

at 1108pm FEB 15  i made the  following post  on the  FB page

**ALERT *** 0Z GFS COMING IN VERY DIFFERENT FROM THE 12Z GFS RUN and much more like the ECMWF / UKMET

This was supported by the Canadian model  0z  FEB 15   run  and like the  European and the new  GFS and  Ukmet   the Canadian model showed no significant snow north of the Washington, DC area.

The model trend continue to show the southeast U.S. Low moving over or just south of Cape Hatteras and out to sea and each one was coming in slightly colder than the previous run on all the models.  After posting the  12z FEB 16 GFS   model  forecast SNOW map on the FB page   I wrote the   following on the FB page   (  which should of  been  under  NEW NOTE     or  posted  here on the   web site )

16FEB 1205PM …   ** 12Z MODEL DISCUSSION 16 FEB MODEL…. VALID FOR FEB 19 EVENT***   and in this  thread I  stated  that so far No model  was bringing the Low north or   heavy snow into any of the big cities of the northeast.  In addition it looked to me that this was going to be a  sw   VA… eastern KY southern WVA    big snow…  And that the rain could turn to  snow for several hours in Richmond but the lack of cold air was going to be a problem east of the Blue Ridge mountains.

Shortly after I wrote that the new 12z  16  FEB  European model came in dramatically colder even in central and Eastern Virginia.  The European model snow map showed a large area of 40 inch snows even through the Richmond metro area.

131PM  FEB 16    ** ALERT *** ALERT ** 12Z EURO BRING IN COLDER AIR TO RIC CHANGES RAIN TO SIGNIFICANT SNOWFALL SUNDAY AFTER 1PM then moderate to heavy snow until late sunday evening … MODEL says 4 to 8 inches of snow Roanoke Charlottesville Lynchburg Richmond Fredericksburg BUT … BUT that is assuming a 10:1 ratio…. if this happens   the snow ratio will  wont be 10:1  around RIC

At this Point I decide to as time the issue a 1ST  GUESS    snowfall forecast  map   at   610pm 16 FEB .

As   we  moved  into the short rain model  timeframe    snow mounts on many the  models began to increase especially east of the Shenandoah Valley into the Piedmont and Central Virginia as the data turn colder and colder with each one.  This was especially true on the  0z      6z and 12z Model runs of the NAM   and  GFS.  It was  at this point that the  short  range models began to show significant snow developing Sunday afternoon across Central Virginia and continuing  to 1:00 AM on the morning of the 20th.

Significant rain events changing over snow with significant accumulations are not likely in Central Virginia but has been known to happen.  But more importantly  the reason for the colder temperature profiles on the shore range models was because the precipitation and the system coming out of the gulf was moving slower .  This in turn allowed for colder air to move southward lay on the 18th into the morning of the 19th.

On Friday morning February 17 I  did a live on air into view with  Jimmy Barret 1140am  WRVA.  My appearance  followed immediately after the  morning news broadcast which featured the some  clown from the  Weather Channel  named  Ray  Stagick.  I have no idea if this guy is a meteorologist are not   but  if he is…  is he  is a pretty awful one.  TWC  committed to inch of snow  or less at the at  the end of the event for the Richmond metro area.    As you can hear from the broadcast..I  went for  2-4  from the city    East and  4 to 8    west  and  sw  and nw of the city and  10″  in  sw  VA.   Still I suppose I should not complain about the weather channel too muchsince they make me look really good.

021712_Dave_Tolleris_1329486354_16656

During the  morning  hours on  15 FEB  all of the Local  TV stations  the their forecasted  snow amounts for Central Virginia in the Richmond metro area   to  1-2”  while  TV 12 continue to show less than 1 inch.  All the TV stations to agreed that western and southwestern Virginia would see several inches of snow and the media stations in the Charlottesville and southwest Virginia / Roanoke markets played up the threat of significant accumulating snow.  Unbelievably even as  NWSFO AKQ began to mention the possibility of accumulating snow TWC  –The Weather  Channel- still refuse to discuss any other outcome except for a rain event with a brief period as snow at the end across central Virginia.

FIRST  CALL MAP   was issued late in the day on  the 17th.

It was based on the  short range data which showed a longer  delay with the arrival of the precipitation.  Most of the other forecasts and model data were   premised on the idea that the precipitation arriving   Saturday night before the cold air arrived.  However the shore range models continue to emphasize a delay with each passing run so that most the precipitation would not arrive until Sunday dawned over the Virginia North Carolina State line and rapidly expanding northward towards Maryland.

However this delay was significant because it  allowed the reinforcing shot of cold air to sweep into PA MD  WVA  and VA.  It was  not that the air mass was dramatically colder but the due points were significantly   drier.   The temperature profiles began to show that the precipitation might start as rain or as an Exe but a larger and larger portion of this event over Central Virginia was going to fall as snow  and NOT rain.  And over southwest Virginia the shore range models are really began to crank out some impressive snow totals.

Winter storm watches and warnings    were  issued by NWS  for all of southwest Virginia the southern third of West Virginia and Eastern Kentucky.

LAST CALL MAP   issued Saturday  18 FEB 7PM EST.

This was  where  I made my first serious mistake. During the last   2 runs of the  European model the model snow algorithm  showed significant snowfall  — 8-12”   in  west to  east  Band stretching from southwest Virginia/ Roanoke east across the southern Piedmont stopping just to the west of Richmond.   Even though most of the other short range models    on Saturday did not show Richmond getting over 8 inches of snow I decided to gamble as a war and extend the 8 to 12 inch band of snow into the southern Piedmont and fairly close to the western side of the Richmond metro area.

This was a mistake.  I thought that the model is increasing the  snow fall accumulations because   the model  has  detected  the colder drier air and the  later  start time which meant that more the precipitation  would actually fall was snow and not mix precipitation or rain changing to snow.

During the afternoon winter storm watch is were issued for all of Central Virginia for  3 to 6 inch snow amounts.

Lastly…  Surely after I issued the LAST CALL SNOW  FORECAST map the last row of the shore range models came out and a  dramatically reduce the northward extent of the precipitation and the amount of significant precipitation over central…  southwest   Virginia and Southern  Virginia.  This causes a reaction from  several uneducated weather hobbyists  –  called   weather weenies—that of course posted the radar trends did not support significant snow getting into central and southwestern Virginia .

AS  we  now know  the 0z   FEB 19  shore range model runs were all completely mistaken.  However the shift was so complete on all the shore range models that I decided to issue a reduced snowfall map.  Even if the 0z   FEB 19 shore range models  were wrong it was clear that was not going to  be a band of  8-12” snows from Roanoke extending into going through the southern Piedmont almost to the western side of the Richmond metro area.

SUMMARY

I believe that I quickly deduce the potential for this event earlier than anybody else based upon my knowledge and study of the  differences between East Coast snowstorms and lower Middle Atlantic snowstorms.

I recognize the progress  nature   of the pattern which would force the system to slide off the North Carolina Coast.

 My FIRST CALL MAP  was best and my forecast on WRVA 1140  was spot on.

 One other note…  I did we see several emails from folks complaining that the actual website had not been updated and appeared to be completely unaware that the updates…  were being posted directly at the FB page.  I will have to make efforts to ensure that annuity is aware of this feature.

ACTUAL    SNOWFALL…

LAST CALL & DISCUSSION RE: FEB 19, 2012

Posted by wxrisk | GENERAL,WINTER 2011-12 | Saturday 18 February 2012 7:13 pm

1700 EST  FEB 18 , 20012… STARDATE   201202.18

 

 

  

 

I am hoping that by  the end of this storm will go into  the record books  and  with  people …   as another  considerable    success   for me   and  WXRISK.COM .  From back in beginning of the week I  was very cautious in declaring that this was going to be a all rain event.  Initially that sort of assertion bought a lot of ridicule with one of the Richmond TV meteorologists saying     ”That contrary to some omission may have heard this week and storms going to be all rain”

This afternoon that same TV station of course had to carry the NWS  3 to 6″   and Winter Storm watches.

Opps!

Its NOT Luck or  hype or  happenstance that this  event has       broekn my  way.   My  reluctance in the declaring this an   “all rain”    event early in the week   was  based upon a extremely well known history or climatology of Virginia Maryland North Carolina snowstorms.  Much of this information I will be posting and providing on the website over the next few weeks now that I have had a chance to catch my breath .      The fact of the matter is that most  meteorologists out there do not know what I know about   Virginia North Carolina and Maryland snowstorms.   But that  is  not all that unusual .

There a lot of meteorologists out there that know a lot more than   me about severe weather and   tornadoes.   or  atmosphere to physics …
or climate modeling.      But during the winter for me  it is East Coast snowstorms in general  of which I given a number of seminars and talks on and  in particular the difference between a Northeast U.S. snowstorm and one for the lower Middle Atlantic region  — North Carolina Virginia Maryland Delaware.

These two animals are not the same thing.  Sure there are occasions where all of these areas…   fFrom North Carolina to Boston see a  heavy major snowstorm.  Some examples of these  are :  January 1996 blizzard…  The great arctic blizzard FEB 11-14 of 1899…   the much  ballyhooed super storm   of March 1993….  The great middle Atlantic    snowstorm of February 1983 and the Knickerbockers storm from January 1922.  But these are exceptions.

The historic  record setting snowstorms of the lower Middle Atlantic   region  was the    JAN 26-27 1940   VA NC  BLizzard   –  did  not bring significant snow north of Baltimore  into the big cities of the northeast.     That  great storm of record in Richmond and all of central and Southern Virginia    was  REAL blizzard and terem was  a  s severe cold wave which followed.  That storm dropped 22 inches of snow in downtown Richmond ….30 inches up by Lynchburg and farmville…   but only 12 inches in DC and nothing north of the Pennsylvania Maryland border.

The March 1-3,  1980 blizzard in eastern and southeastern Virginia or  the one in February 1-3, 1980  or the one  in Jan 1-3  1980  were all total misses   for  the big cities of the Northeast.    Even the surprise blizzard   of January 25,2000   the  brought     huge amount to snow to of Charlotte   (20 inches )   and the entire state of North Carolina … 1 tom2  feet almost all Virginia into Maryland and Delaware …but the snow mounts dramatically fell apart over the big cities of the northeast.

Most of the meteorologists that I have talked to  and/or get information and discuss these synoptic patterns with me   have agree with the argument that I made back the beginning of the week that this coastal storm would NOT have a chance to turn the corner to come up the coast to bring heavy snow to Philadelphia New Jersey New York Boston and New England.  The reason being the system crashing into the West Coast  would act as a kicker — a force of energy which would show the system over the southeast U.S.  off the North Carolina Coast.

At this Point I am pretty much done looking at various weather models and it’s almost time for  “now casting”.  It is also however time to take a look at possible scenarios regarding my forecast  and  forecasts in general as to    WHAT   COULD GO WRONG:

1.  NORTHERN EDGE OF THE SNOW …  some of the 18z  Models and the   12z Saturday European Model do   have snow getting into Washington DC Southern Maryland  the lower Maryland Eastern shore … Southern Delaware even into Cape May NJ.    But not all the models agree about. There could be   pretty sharp cut off on the northern  edge.  It’s possible Washington, DC could see 4 o 5 inches of snow.

2. LOWER  MD  EASTERN SHORE…  Over the past 72 hours as we have moved into the short range models  …all the data has showed that the heavy snow areas in western .. nd Central Virginia narrow  to   a  “V  shaped  point  “    over the lower Maryland Eastern shore.  Some model data shows that the lower Maryland Eastern shore   may  be too warm for  the snow to stick …   but other data shows  there there  could in fact be a  2 to 4″ or  3-6 ” band of snow  over Dorchester   Wicomico Somerset and Worcester perhaps into southern Talbot and  Caroline  counties of the lower Maryland Eastern shore and   Sussex County in Delaware.

3. DELAYED START TIME …  Earlier in the week it looked  like the rain would come in   before  dawn Sunday over much of the southern third of Virginia and of course temperatures would  still be way too warm for the precipitation to fall as snow.  However over the last 36 to 48 hours the models have delayed the start of the precipitation.   By Sunday g 7:00 AM the rain is just across or along the Virginia North Carolina border.  This allows more cold air to get into the commonwealth  and   this air also  will have   lower  Dew points so that when the precipitation begins   and the  air   saturates   — where the temperature and the dew point meet — it does so at  or  below 32°.

4.   TEMPS  SUNDAY NIGHT IN CENTRAL VA….  I anticipate temperatures to drop down to 32° for most of the storm Sunday evening…  some areas might get as low as 31.  Either way it will be just cold enough for this snow to accumulate.  But  the  snow will  be a heavy wet snow especially the beginning and that will cause   some compaction with the snow on the ground.  In other words suppose you measure the snow at one particular time…  at say   4″.    But then you measure it 2 hours later and it’s snowing like hell  but  you  only   measure  5 inches.   This could be   the  type a storm which presents real problems with regard to measuring snow amounts correctly.

 

On a sidebar let me point out some problems that exist  with the forecasts that I see from NWS.  Now  I hope this does not come across as a NWS  Bash…  because that is not what it is intended as .  I have gotten a lot of emails and face book postings regarding the forecast for southwest Virginia especially in and around Roanoke  and Lynchburg.  The problem is that the official forecast from NWS is correct.  Roanoke for example is under a winter storm warning for   at LEAST   4-8 inches of snows..  and  the   term  ” at least” implies   it could be little more than that for Roanoke.  That is a GOOD forecast.

 

BUT some of the NWS sites however do not show that.  As of 5:00  or 6:00 PM  Saturuay …after the winter storm warnings have been issued by the Roanoke/ Blacksburg office …other web sites was still showing this.

As you can see this forecast so calls for 2 to 4 inches.

Many TV and radio stations including some of the weekend idiot weather people in southwest Virginia apparently did not know about this confusion.  So they been telling their viewers winter storm warnings for Roanoke  with 2 to 4 inches of snow.  This of course makes no sense since the criteria for winter storm warning in Roanoke and southwest region VA is more than 4 inches of snow.  I do not know what the problem is but I do know that this sort a communication breakdown is very bad news for professional meteorologist everywhere and for TV and NWS people as well.  You cannot  have one end of the body not knowing what the other end of the body is doing…  This needs to be fixed  right away.

 

Second I don’t understand the forecast for Lynchburg.  If you look at the zones here in southwest region VA  you will notice that Lynchburg and counties to the north are not in official winter storm watch are warning…  But counties to the east and southeast ARE in a winter storm watch.  This makes absolutely no sense whatsoever.  In addition all the data even the warmest models show at least 6 inches of snow in the Lynchburg area accumulating and much of the data shows 10 or 11 or 12 inches.  Now you could argue that Lynchburg is not to see that would snow.  But how then do you argue that areas to the east which were largely would be a little warmer  — areas such as farmville and Prince Edward county   are in a  winter storm watch?  I sure hope that is fixed soon because that is a busted forecast waiting to happen.

 

 

1ST GUESS MAP for FEB 19 WINTER STORM

Posted by wxrisk | GENERAL,WINTER 2011-12 | Thursday 16 February 2012 5:07 pm

REVIEW OF THE MODEL DATA 15 FEB 2012

Posted by wxrisk | GENERAL | Wednesday 15 February 2012 10:00 pm

2200  EST  15 FEB   2012

I am often asked a question like  ” what does my  gut say…?”   or   “what is my instinct about this particular event ?..”    My response has been and will always be I do not forecast by gut or by emotion or by instinct .  There are some other well known meteorologists — and a lot of   weather   weenies–  who do that and  it usually results in disaster.  By committing to  one particular  forecast Model or  idea days ahead of time …   their  bias  becomes involved the forecast process.   When one model comes out which shows what they think is going to happen… they  Have  TO  latch onto   to that idea it because they have decided days out to go with that particular solution.  In other  words  by   committing so early  to only solution  one loses  the ability  to think   critically.

DT ‘S MEDIUM  RULE #3…   when  ANY  Model … which has been showing  XYZ   for many consecutive runs in a row…  Suddenly shifts and in 1  run shows  ABC….  The other pretty good that that shift is wrong…  Unless all the other weather models also show the same sort of  BIG shift.

The reason why this rule works is that in the current state of  numerical model prediction   — weather models– they are sufficiently accurate and of high enough quality that  it almost all cases if one model shows a shift of significance the other models will fairly quickly follow suit.
This is why I NEVER  Forecast by instinct or Gut.  This is why   REFUSE  to even  consider   the GFS past 72   -84  hours hours when it comes to East Coast winter storms.      Now that being said    I am sure others e are going to manipulate or lie or change this assertion into something that I haven’t said.     I do  NOT have a problem with the GFS model for certain weather patterns   OR  once  we are within 84 hours.  The  0z 15FEB   GFS  model run  was a massive …severe  unprecedented shift…  sSifting the coastal Low  from  the Georgia Coast …  suddenly  300 Miles to the nw  over  ATL…  from passing south and east of Cape Hatteras   to passing   west of Norfolk … fromn showing NO precipitation of any kind north a Washington, DC …  to driving heavy snow and rain into New York City Albany and will Willaimsport  PA.   The fact that you may be living in the northeast big cities and the  0Z GFS  is the picture perfect and one that you want to see for your location does it mean that the solution is a viable.

The proof ? all the OTHER  weather models did not show any significant change in their track or forecast and the updated  6z GFS has gone back to the southeast U.S. coastal solution.

This is supported by the Canadian and the British models 0Z  FEB  15   runs    as well as the 0z  ECMWF     and  the 0z European  Ensemble….  All   showed  ABOUT  the same  SORT  of thing”    the surface Low  tracking along the SE US   coast   in a  ENE direction   then over   or close to  Cape Hatteras.  There   was   absolutely no supported  at all for the ridiculous  0z GFS . None.

In fact the 0z FEB  15 European model had no precipitation of any kind north of Fredericksburg…  The Canadian and the British models do not have any significant snow north of the Washington, DC Baltimore area.   Again I Hope  realize  that   reporting and  discussing   the weather models does  NOT  mean that   the point I am Making   is   MY forecast..     I am  CERTAIN that this will    event wiill become  a mjaor    Precip  event .

We  saw  the same sort of thing   with the 12z GFS  ..  Another solution which was unsupported by even the GFS   Ensemble .  It became so bad   that at midday   15 FEB  HPC had issued a special statement regarding the bizarre scenarios and solutions being proposed by the 12Z  15FEB  operational GFS run.

From HPC Model discussion-THE GFS APPEARS TO HAVE WORSE INITIALIZATION OF THE TROUGH’S PLACEMENT OVER BRITISH COLUMBIA AND NUNAVUT THIS MORNING COMPARED TO THE NAM/ECMWF. MEANWHILE…THE GFS IS MOST AGGRESSIVE IN ALLOWING AN UPSTREAM PERTURBATION CURRENTLY OVER THE PACIFIC TO CUT THROUGH THE SHORTWAVE RIDGE OVER THE CANADIAN ROCKIES ON THURSDAY…WHICH THEN PHASES WITH THE NORTHERN STREAM AND SLOWS THE ENTIRE GFS SOLUTION. THE COMBINATION OF WORSE INITIALIZATION AND QUESTIONABLE AND EVEN SUSPICIOUS PHASING OF THE SEPARATE STREAMS IS SUFFICIENT TO DISCARD THE GFS

But     the   Model  fiasco   last night with the  0z 15 FEB GFS  and  12z  15 FEB GFS  does  emphasize again why I think the  GFS  model …  with espect the East Coast winter storms … is a  piece of  crap..  Note that so far  NONE  of the other medium   range large scale models has shown any sort of  HUGE  wild  swings   in  6  or 12 hrs time increments.      NONE.

Increasingly this looks to me more and more as a Shenandoah Valley /  western VA….and Northern Virginia snowstorm    then up into   DCA/ BWI  area  and possibly  into  southern NJ  .  Richmond I think is going to be more wet than white but I am not absolutely convinced of that all of the event is   going to be all rain   for  central VA.

The area from Lexington south to Roanoke then down to   Hillsville poses of what I think to be the biggest challenges forecast.  Clearly areas which are in elevated terrain have  much better chance of seeing or staying all snow and clearly areas which are and north of interstate 81 have a even better chance of seeing snow…  Either in its entirety or a mixture of rain / snwo  going over to snow as the cold air is pulled into the system.  Once you move north of Lexington and Lynchburg there should be and of cold air east of interstate 81 so that the rain

Of course if one follows the   12z  FEB  15  European model…  And if you have access to the precipitation panels you  will have  seen that very little precipitation falls north of a line front Richmond to Roanoke Virginia.  However the European  Ensemble is much weather and has a large significant precipitation shield …with    precipitation amounts   of  0.25″    that extends    to the Virginia West Virginia border as well as the Maryland Pennsylvania border and into Southern New Jersey .

There could of course the snow to the north of that…  into Philadelphia and New York City.   In fact I suspect is probably going to be even though as a deceiving most of the TV stations in those markets are not forecasting snow into those cities.  That being said a honest interpretation of the pattern and what the model data has been showing in trending   – again ignoring all 4 runs of   15 FEB GFS    –   0z   6z   12z ans 18z  – shows that this is not going to be tracking up towards Cape COD with a benchmark.  That sort of thinking and analysis is just  outright delusioal   and  shows a  poor grasp of basic meteorology .

That  is not to say there aren’t meteorologists out there who are forecasting that but the data does not support a track of the   Low to the benchmark of   40N/ 70 W.   And more importantly the overall 500 MB clearly does not support that a specially with a large  closed 500 Low over  se   Canada.

12Z RUN OF FEB 13 GFS ENSEMBLES START TO COME NORTH

Posted by wxrisk | GENERAL | Monday 13 February 2012 2:00 pm

1330  EST   13  FEB  2012

click on the image to  see   FULL SIZE

 

WELL ITS SORT OF WINTER …

Posted by wxrisk | GENERAL,WINTER 2011-12 | Monday 13 February 2012 4:07 am

2230  EST  12 FEB  2012… STARDATE  201202.12

 

For most of this winter’s been pretty meager pickings if you are a winter weather or snow lover here in the Eastern CONUS region and if you are south of DC it’s been really slim pickings. The arctic cold front and the thunder snow and squall line which came to one Saturday certainly was exciting. I personally have not experienced under snow over 20 years… and I consider thunder SNOW o be better than cheap sex.

I made a comment on Saturday afternoon about the thunder snow and the snow squall on the FB page which I subsequently removed because it was not being taken the right way. The potential for a significant East Coast event FEB 11-12 I started referring to back on JAN 28. At first I was quite bullish on the system and thought it had the potential to bring a major snowstorm too much of the Middle Atlantic and New England coastal areas.

That did not happen.
So in one sense you could argue ...”well DT you sort a Busted on the long range forecast regarding the system“.     I would argue however that to make such a judgment shows that the person making that judgment is probably an idiot.     It is not that the assessment is wrong per se since there was no major snowstorm on the East Coast February 11-12.     The problem is that given the understanding of  weather and what can or cannot be forecasted with any sort of accuracy… it is not reasonable to expect a forecast from 14 days out to have the same accuracy as a forecast 2 days from now.    Given that my focus on the potential for a significant East Coast storm February 11 -12 …started at the end of January I think it was a pretty good forecast.

To be sure the GFS model is forecasting an East Coast winter storm of some type for another every three of four days.   But most of those events simply disappear are never come close to developing.   With respect to the February 11 Low… all one has to do is look at the satellite pictures and the surface maps from Saturday morning to see how close this system was to dropping massive amounts of snow up and down the East Coast.    The major costal storm DID develop but it also developed too far off to the east.      But it was a very close run thing and given the forecast was made 2 weeks out… I think it was a pretty good call.

In the short range –with regard to the Saturday event and the thunder snow and arctic front squall line– my view was that I don’t believe the local weather media in the Richmond area was giving enough impact or focus to the arctic front.    Once we reach the short range forecast time frame of this event – FEB 9 and 10 — I repeatedly emphasized that the main impact of this whole system was not going to be the coastal storm for Virginia and Maryland but would probably be the arctic cold front with the potential for heavy snow squalls and a possible flash freeze with the arctic front arrival.

The flash freeze of course did not happen for most areas but the snow squalls did and as we all know there was thunderstorms in the snow squalls! From my point of view… and this is just my opinion… saying something like ” we might see some snow showers with a cold front this afternoon when it arrives”… is technically OK but it’s not really an accurate forecast. And if you are going to go on air during the evening news and explained everybody what thunderstorm is and how it forms then it seems to me that that expertise could of been applied to emphasizing the potential for heavy snow squalls with a cold front arrival.

I know that some think that I am     “bashing”    other Meteorologists. I don’t think I am doing that but I guess it comes across that way. My goal here is to focus more on getting the forecast information out in a better way without destroying the signs of meteorology through a lot of tabloid hype and meteorological bullshit.

Several years ago there was some interesting research done about how the general public view meteorologists.  One of the things they found out is that while every body has their own “favorite” weather person or meteorologist that they listen to read or watch ( or some combination there of )… when the weather forecast goes bad the general public as a tendancy of thinking that all meteorologists either made the same or similar type a forecast or that they ALL busted.    I am not really sure why this is the case. For example if you take your car to the mechanic but the mechanic cannot figure out what is wrong with your car… very few people in the general public assume that all car mechanics are as bad as the one you are using. No one assumes all Car mechanics are of the same skill. And this is all the case with regard to how the general public views other professionals such as attorneys or doctors.    WHY  the general public has a different view about Meteorologists I dont know…. though I have some theories.

This is a kind of a pet peeve with me… but on the other hand it also helps me with my business in the grain and energy markets. Because there is so much bad medium and extended range forecasting going on out there and these inept forecasters seem to get a tremendous amount of publicity… When they come across my stuff many of these individuals are well… a little shocked.
For example my initial forecast for prolonged periods severe cold in Europe was made back in Mid January. At the time I dont think anyone else was calling for this sort of severe or prolonged cold ( but I coud be wrong about that…)

Or when it came to the debate about what was going to happen in February 2012 in the eastern CONUS… I opted for a short duration interval of 1 to 2 weeks of seasonally cold temperatures …nothing too severe… that would be over by the middle the month. Yet those forecasting a “Fabulous February” with temperatures dropping to zero in Boston and Chicago are continuing to bang the drum about how impressive week old the second half of February and March 2012 are going to be over portions of the eastern U.S.
Back in the early portion a January it look like that the pattern was getting ready to undergo a significant change. I had made several posts here on the web site and on the FB page… about how it looked like the jet stream is going to go undergo a significant amplification over the Bering sea into the North Pole region which would force all sorts of changes with regard to the +AO and – NAO. However by mid January it became obvious that the models were wrong and that the pattern was going to develop and a vastly different way.   It happens.

But you do NOT  keep holding onto the idea that severe cold is coming if the pattern has not changed.    If XYZ are causing the mild snowless winter pattern over the eastern CONUS…. and you forecast XYZ to change to ABC… well that’s great. But if ABC never shows up and the pattern does not change… then give up on the cold scenario already. Otherwise it looks like you don’t know what to doing or you are trying to BS folks so they hang on for another month while you rip them off.
Now lets focus a little bit on the potential for this event on February 19-20. First I am not YET committed to this event happening. Right now this threat is just a possibility. A THREAT… No more… Does that sound wishy washy?

Too friggin bad. As I said before… You don’t get extra points and you don’t win the game by making the first outrageously bad or stupid forecasts that you can. This is been a tough winter and it’s not been the same as the last two winters where it was easy to see major snowstorm events coming 5…6… and 7 days out. Whatever happens or does not happen over the Middle Atlantic areas on February 19-20… the fact remains that once this event or threat is gone… the last 10 days of FEB for much of the East Coast will feature more above normal temperatures. Perhaps it may mean the end of winter for much of the eastern CONUS …. except for New England .

The   FIRST  KEY POINT  we have to focus on is the system which tracks up through the Midwest and into New England on February 17. That system will bring rain and mild temperatures to the East coast but once it moves up into southeastern Canada most of the model data shows the system stalling over Maine and or southeastern Canada… a feature which I call the “50/50 Low”. This in turn allows for cold air to come pouring southward out of Canada across the Great Lakes and into the Ohio Valley and the Middle Atlantic states.    If there is NO “50/50 Low”…. then nothing is going to happen on February 19 and 20 with regard to any sort of wintry weather on the Middle Atlantic Coast.
The SECOND   KEY POINT    has to do  with the southern shortwave or piece of energy itself.   Right now the system of course is way out in the Pacific Ocean and the weather models are guessing or estimating how strong or weak this feature may be.     A much stronger system coming through California and the southwestern states and the southern jet stream would of course increase the chances of a significant Low pressure area forming on the Southeast U.S. Coast February 19 .    But there  is no guarantee that is going to happen — the model data could be wrong and this system coming in from the Pacific on the southern jet stream could be quite weak.

THIRD if the 50 /50 Low is too strong or too far south then the southern short wave energy DOIES get crushed or supressed and NOTHING happens except for some rain over TX LA MS AL SC and GA.

When one is faced with this much uncertainty you have to walk a fine line.   At this   point   when faced with this sort of  uncertainty what  I try to do is set of some deadlines  or    some benchmarks.    Most of the answers for the potential   threat  or  mystery regarding February 19 – 20 will probably begin to show up around February 16 -17.     By that time I will have a pretty good idea about how strong the southern shortwave will actually be…   and  most of the Model data will have a pretty good idea of how strong the 50 50 Low will become and where its position is going to setup.

 

FUJIWARA COMES TO EUROPE

Posted by wxrisk | GENERAL,WINTER 2011-12 | Saturday 4 February 2012 11:05 am

1100  4 FEB   2012   … STARDATE  201202.04

 

The extreme winter pattern that has developed over Europe is locked in position and shows absolutely no sign of breaking over next 7 to 10 days.  Complicating this is an development of a prolonged period of extreme winter weather ….a real historic old timers massive BLIZZARD…   over Southern Europe which is going to continue for another three days.  This is just exceptional weather and one that is meteorologically  extremely significant and a very good learning experience for anybody wishing to understand the nuances of European WINTER  weather.

What makes this extreme winter weather  in Europe  even more significant  is that the  atmosphere has responded to the arctic blast and a deep trough   in the Jet stream over central and Eastern Europe …by building a equally strong  Ridge  over the Azores and Spain.  This massive Ridge is  BLOCKING the deep trough over central and Eastern Europe and Western Russia/  Ukraine  from moving   west .   And this includes the 1060 mb  massive  Arctic HIGH over  NW Russia .   There  is  literally NO place for the Deep trough in the Jet stream   with  the  deep arctic cold  or the center of the massive  HIGH over Northwest Russia ….to move .   In other wirds  the arctic  cold    has No  place to   drain or  “spread ” out  like  it  does in the North America  when  Canadian arctic HIGH pressure systems dropped out of Canada and move towards the VA  or Texas .    Instead  it just sits  there   and it’s colder and colder as more and more mass of snow continues to fall.

This image shows the temperatures from yesterday afternoon on February 3 and this morning February 4.  Remember these numbers are in Celsius NOT Fahrenheit…  But there are plenty of temperature converters  you can access through Google to convert them if you cannot do the mass in your head.  -18c   is    ZERO degrees F   …-10C  =14F

As you can see most of Southern Germany was at or below zero as was all Poland.  There were several locations in the western and Central Ukraine as well as Belarus which dropped  down to an astounding  -33c this morning.  And many locations on the afternoon of February 3 in France   (of all places)   did not break  32 degrees  F.   Most of Germany saw max temps in the teens and single digits as the western  Poland  Austria and Hungary.   Many locations in the Ukraine and Belarus did not get above 04 Max temperatures yesterday and if you look at the readings in the the Balkans even south of the Danube their locations which did not get above 0  degrees   F  !!!

This image shows the European and Asian temperature anomalies from last night.  The BOTTOM  map shows the actual  850 mb  temps and you can see how impressive the cold most of Europe is…   while the  TOP map shows the temperature anomalies relative to normal and the dark purple   and violet colors s show the extreme anomalies over Western Russia  …eastern …central… and now Western Europe.

The morning satellite picture shows a massive clouds swirl covering southeastern Europe.  There  is  widespread heavy snow and high winds and now blasting that crap out of most of the Balkans and the Western Ukraine.

The surface  map from overnight tells the reasons WHY  quite nicely…  This is from the European model and we can see that last night there was a moderately strong area of   LOW pressure over Southern Italy…  and   the Large arctic HIGH of 1059  MB over Northwest Russia near Saint Petersburg.  If you look of the BLACK  Lines which are the Isoabrs … you can see that the arctic HIGH  pressure extends all the way into France and Eastern Spain.  The interaction between the surface low  of 1002 MB  and the   1059 HIGH is producing strong east winds across the Balkans feeding the moisture into the elevated train and producing massive  snow falls this morning on the surface maps and reports.

If you take a look of the RED lines …which of the jet stream configurations…  you will notice that there is a Upper Low associated with the surface Low over Corsica and Sardinia  -   which I have highlighted in darker GREEN.   But there is a second ULL over   Poland  and the   western Baltic  Sea….  which is going to get pulled into the big Low over the Mediterranean over the next three days and produce ANOTHER   blizzard .

Here we can see that on the European Model   valid  for 72 hours from now.  The Low that was over Italy is  now  over Greece and it is Much  deeper..995 MB.   What has happened here is that the Low over Italy has strengthened as the Upper Low over Poland has been pulled into the southern  Upper Low.   This process is known as the Fujiwara effect  and while it doesn’t happen very often at the surface it does happen more commonly at the upper levels the atmosphere.

Even more impressive is the pressure gradient!!!!    The 1061 massive    Arctic HIGH  is still there  and it has moved at all…  while this 995 Low is trying to move into the Bulgaria and Romania ans from Greece.  Of course it can’t but the interaction between them is producing a lot more Black Lines an extremely strong winds across all of southeastern Europe and into the western half of the Ukraine.  Also  keep in Mind the  blizzard is still raging past 72 hours!!!!

Also take a look at what’s going on over Spain   …the Azores and the United Kingdom.  The ridge in the Jet stream   there has continued to expand and push towards Iceland and the west coast of Norway.  Keep in mind the  Teleconnection  here…  This massive  Azores  Ridge means that the system over the Balkans can become very strong and deep and also ensures a prolonged extremely heavy snow event because neither the arctic high or the deep low over Greece can move.

This next image shows the GFS snowfall  forecast for the next 72 hours and most of the Balkans and Western Ukraine are going to disappear under a blanket of 2 to 3 feet of snow because of the current heavy snow falling over the region….  And the 2nd massive blizzard which is going to start Sunday.

Finally this Last image shows that changes snow cover for Europe over the next eight days.  The image on the left is based upon the snowfall as of this morning … February 4…  The image on the right based upon the model data eight days some now February 12.   These maps  speak for themselves….

 

WOW.. just    wow…