0800 14 NOV  2011

If it wasn’t clear last week in the weather models… it certainly is clear now:     there is  little chance of a turn towards a significantly colder  pattern over   any portion of the CONUS before December 1.  Again that in itself is not that unusual   per se.  But obviously as we move towards Thanksgiving and  the last   days of VOV  there will   be a big emphasis on whether or not we are going to see a significant large scale pattern change.  Last December that  is exactly what happened…  but  back in 2007-8   the   pacific jet   never let  up  and all of the DEC    cold in the    eastern  CONUS forecasts busted horribly.

In  looking at the “overall”   pattern I do see some changes of current  pattern. But with respect to affecting sensible weather conditions  in the  Conus….  there  is  not much to get excited about if you like cold weather.  It  is important that as a meteorologist we communicate in a clear and effective manner.  So while I can talk about changes occurring in the overall pattern at the high latitudes which over the long term could be more positive towards   getting a colder  pattern… the fact  is that  for most people this will sound like a bunch of esoteric   gobbledygook  because  their forecast shows  more  mild  temps. From the  average person point of  view   there  appears to be  no significant change in the overall pattern.

If we compare the current hemispheric  500 MB  map   as of 0z NOV 14   to the one from  NOV  7 we do indeed see significant changes.   The  PV has split which is what most of the models were  e forecasting and we now have one of the PV centers moving into far northwest portions of North America    (the  north  slop of    eastern Alaska/ Yukon).   The   other  PV has  retrograted and is now moving towards the north side of central Siberia on the arctic circle.   And we also seeing the widespread introduction of arctic air across all of Central  and Northern Canada which is something we did not see last week  or the  week before.  This is leading to increase in snow cover across Canada as well.  

 Another key aspect to the overall pattern is the powerful European or Scandinavian  Ridge.  Last week most of the model data show this Ridge  retrograting  into Iceland   or Greenland  but clearly that is not happening on any the model data over the weekend or this morning and that’s one of the reasons why the pattern change at the high latitudes is not working its way down to the mid latitudes.

Part of the problem is that the new polar vortex over Northwest North America splits into two sections. The  Eastern   portions  slides to Eastern Canada by the end of the week and moving towards Baffin island and the Davis straits by Day 7.  This movement initially causes a  moderate   trough to develop over the eastern CONUS   but once this feature moves into Eastern Canada were labrador in actually  cuases the NAO  to  flip  back to Neutral or  Positive and it also kills any chance of the Scandinavian   ridge   retrograting to Iceland.

This is reflected in the the  Teleconnections  Indicies…   http://raleighwx.americanwx.com/models/00zlinegraphs.html

However the western portion  of the  North  American  PV…. continues to move from the north slope of Alaska southeast into the gulf Alaska and along the Alaskan panhandle  by  day 3.  This feature slides down towards Vancouver Island and the Pacific Northwest    by day 7.     It  is a very intense vortex and if this was the middle of December  there is no doubt that this feature bring a major snowstorm to locations such as Vancouver and Seattle.  It still might give an how  impressive this feature is.   A piece of this energy  breaks off and develops  a  significant surface Low  that tracks of the western high plains this weekend with the arctic air pressing south across sea was Canada border into Montana and the Dakotas.  This will probably be the first serious winter storm for the Upper Plains of the season  — there was a moderate one last week .

By day 10  the  operational European and the European  ensemble show a dual center pattern with one PV  over central Siberia and the other one located over northwest Canada –perhaps in the Yukon. The PV  over   the  Yukon is clearly was stronger on most of the model data with  its  value     below 500 DM .   The Teleconnections from this intense vortex over far Northwest North America of course supports a strong southeast U.S. to ridge so all of the Model  data here  apears to be  very consistent and  meteorologically sound. 

In addition if you take a look at the  500 MB   height lines over the north Pacific you will see that the extremely strong central north Pacific    positive   height  anomaly  — the   Ridge   at 588dm– is located surprisingly close to the   498  dm   very strong and negative  height anomaly over the Yukon.  This of course is causing the Pacific jet to become squeezed causing ncreased  velocities to a extremely powerful  180 knots on the 0z GFS   at 192 hrs.    And  having the jet streak slam into    the  West coast  / br Columbia   ensures the mean trough stays on the West coast and  the  the cold air   building Canada  cannot possiblly   drop south of the   US Canada  Border .

Clearly the impediment in terms of getting the pattern to turn significantly colder is the extremely intense polar vortex over the Yukon.   This  fat  pig   has  got  to MOVE  or slide    southeast into   north central  Canada.  As long as that feature  is in  that part of the western hemisphere the pattern is absolutely no chance of changing.  This position for a  PV  has   long been know  as the Kiss of  death if one is forecasting any sort of sustained colder outbreak were pattern developing over the eastern half of North America.  Of course there have been plenty of winters where the vortex up there in northwest Canada in November has moved  to the southeast  which ends up altering the entire pattern.  But as long as that feature  is  there and the 180  knot    long jet streak ….     the central and eastern  CONUS stays Mild.

1000  EDT   NOVEMBER   10

 Why is it that whenever I start   some sort  of  new venture ….all sorts of weird stuff seems to happen …both culturally and with me personally? …. Just one of those things I guess.

I will start out this morning by taking a look at some of the MJO forecast models and see how or what they are forecasting in the current MJO pulse over the next 2 weeks and what… if anything …they that can tell us about the evolving pattern. The Current MJO is of moderate intensity and located in phase 6.    This corresponds to the map   below where we can can see several important features.     There is a large area of strong positive height anomalies over Scandinavia and over the north slope of Siberia… And a strong negative high anomaly over the gulf Alaska.

http://raleighwx.americanwx.com/MJO/NovemberPhase6500mb.gif

In the general sense this appears to be a fairly close match to what most of the medium range models of forecasting over the next several days with the strong negative anomaly developing in the gulf Alaska as a series of strong Lows crash into Western Canada the Alaskan panhandle and eventually down by Vancouver and Seattle day 8-9-10.

In fact the operational European and the GFS Models do show a pretry potent system traveling down the Alaskan panhandle and slamming into Vancouver and Seattle November 19 – 20.    It does so because all the models are developing or expanding a Ridge over the Bering sea into Western Alaska.    Right now the model data shows 850 MB   temperatures clearly cold enough to support snow even in downtown Seattle and maybe even Portland…. which in mid November is pretty darn usual. The development of this Ridge at 500 MB allows for the first large cold arctic High of the season in Northwest Canada .

So whats happens with the current MJO impulse?

The first link here represents the NCEP GFS Ensemble mean which is forecasting the current impulse to reach phase 1 close to region 2 by November 24
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ncpe.shtml

The operational European MJO  model shows the impulse collapsing by the time they reached the thanksgiving weekend…
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ecmf.shtml

And this trend is supported by the European MJO ensemble mean and spaghetti plots
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ecmm.shtml

Therefore if we assume that the current MJO impulse will make it to at least PHASE 1 and POSSiBLE Phase 2….  We end up with this sort of pattern.     In PHASE 8 we can clearly see strong positive height anomalies at 500 MB increasing southeastern Canada…  and over Northwest Russia into Scandinavia. In addition we can also see strong negative height anomalies over the Siberian side of the arctic circle— which is currently were the PV is
http://raleighwx.americanwx.com/MJO/NovemberPhase8500mb.gif

By phase 1 however we see a strong positive height anomalies developing over southeastern Canada into Greenland and extending into northwest Scandinavia. This would count as a -NAO.    The very strong negative anomaly just to the west of the  UK   ould also be significant as would the intense Neagtive  anomaly over eastern Siberia.  http://raleighwx.americanwx.com/MJO/NovemberPhase1500mb.gif

 The PNA and NAO plots from ERSL show a moderately negative –NAO but it extremely strong a persistent West Coast trough / -PNA.   http://www.esrl.noaa.gov/psd/forecasts/teleconn/images/compare.pn.png

Even though the WPO changes phase sometime  around the Middle of   the month the EPO does not.   It moves into a persistently strong positive phase which of course means more strong negative anomalies over Alaska and the Gulf Alaska and above Normal Heights over southeastern Canada.    http://www.esrl.noaa.gov/psd/forecasts/teleconn/images/compare.we.png

This sort of solution matches all of the model data in the 11 to 15 day from the GFS and European ENSEMBLES .    What we are left with then is pretty neat tidy package of strong model agreement that matches the MJO November pattern for Phase 8 1 and 2.

While the strong ridge over the eastern half of North America and especially over the CONUS is going to be very slow to move out with a +EPO and a strong – PNA …    this pattern will allow for the significant buildup of arctic cold and rapidly increasing deep snow cover over the next two weeks for most of Canada.   If you are bored looking at thisn pattern east of the Rockies you might want a look at the increasingly cold temperatures and deepening cold air mass across all of Canada rght up to the U.S. Border.

One last point is to focus on the connection between the strong Ridge over the dateline into the Bering sea and the strong Negative anomaly over the British Columbia region.    I am sure it’s obvious to many but I thought I would emphasize the point that until the Ridge in the north Pacific over the dateline / Bering sea shifts or e altars position ….the -PNA is not going anywhere.   On the other hand if you are in Seattle… over Portland… Boise   Spoakne    Redding  Calif  into the N Rockies your winter is going to start early

0800 EDT   9  NOVEMBER

First let me start out with a couple of announcements.  There is going to be a new subcategory  on  the WXRISK.COM   page.. called  HARDCORE

This subcategory will be dealing with the serious meteorological  analysis.  I hope to update this subcategory/ page   EVERY DAY  around 0700  EDT  or so.   It is going to be primarily aimed at energy meteorologists   Grain Meteorologists   TV Meteorologists  and  all those who have a need or dseire to read    serious hardcore meterology.   It will be free  for all.   The subcategory HARDCORE    will NOT  be for  the layman or average  person  and I  hope I will make that  make that quite clear.      For  average folks   that are NOT     Hardcore   weather   nuts or  professional   Meteorologists …     I will be using   WINTER  2011-12  subcategory/ page. 

Increasingly there are more signs that a significant pattern change is coming for North America.  And that even though the next 7 to 10 days over most of eastern  CONUS — and  eastern Canada  for that matter — are going to see some pretty impressive warm temperatures for the middle of November— things are starting to move and the pattern is beginning to shift. 

In the last discussion  -NOV 5– I pointed out the several key players hemispherically  which have to change with regard to the current pattern…  in order for some sort of reasonably winter like hemisphere pattern to develop. 
IMAGE # 1  we see TWO  Maps ….   the Map on the LEFT  side  is the CURRENT  hemispheric  pattern as of November 8.  This is from the 12z initial European model  (ECMWF)    ENSEMBLE  and again of highlighted some important key features.

As I pointed out back on Saturday we still only have one large intense Polar Vortex which is situated over the northeast the slopes of Siberia.  There is no PV  anywhere in the western hemisphere…  which is  one of the primary reasons why the pattern has been so Mild.  With the polar  Vortex  on the other side of the arctic circle there  is no large pool of cold air in the western hemisphere to draw on.  We can see this on the map on the right side….  The white line shows the boundary of the arctic air and as you can see it’s extremely far to the north a specially for early and middle of November.    So even if there  was want to get a large cold High to come south it would consist of mile Pacifc  air.     In addition we can see the strong ridge over the eastern third or eastern half of the  CONUS  and the Scandinavian rage extending from the Ukraine  into central and northern Norway and Sweden.

In IMAGE #2 …     there are  3 maps…. all   based on the 12z   ECMWF of 12z  NOV 8… and  all 3  are valid for NOV 15.  The first map again is a large scale hemispheric  view.  First we can see that the model is showing that the PV   is SPLITTING  into two pieces. 

 SECOND  the RIDGE over Scandinavia has now moved into the UK and is building towards Iceland.  This movement counts as a eastern based  – NAO feature. 

THIRD… the   strong ridge over the eastern half of the country has been pushed more towards the southeast and  Northeast  US coasts. 

  FOURTH… We can clearly see a massive trough developing over western and Central Canada….  and the big ridge  over the north Pacific  is sliding WEST  towards the international dateline.  This is allowing for the mean trough which has been over the West Coast to slide into the Rockies.

 The   2nd  map  in IMAGE  2…  Shows the large scale cold air pouring across the Arctic circle into western and North Central Canada for the first time this season.  The third map is just a more localized view of this…  with the arctic cold finally poaching the was Canada border for the first time this season. Also  note how  very warm it is  the Southeast  and Northeast  US.

IMAGE  #3  is the day 10 European map…  Valid for November 18.   Again we have three maps in image number 3 to look at.

The first image shows the hemispheric projection of the day 10 European.  We can clearly see two polar vortexes have  formed….  with the first or original   PV   now located over Central Russia near the Ural Mts.  This is important because if you recall the original position was over  north  side of eastern Siberia.  This movement  of PV #1  to the   central Russia   is  allowing to  Pac Jet to relax—   meaning that the Pacific jet is more likely to buckle or change shape.     And note that the powerful southeast U.S. ridge is now mostly out into the Western Atlantic Ocean.

The second map  in  image #3   shows the arctic air now moving into an across the U.S. Canada border…  And that the Arctic air is rapidly building up too impressive levels over all of western and North Central Canada!  Again why is important?–  IF Canada does not have any colder air in it…   it neither will the U.S.

The  Third image   is  again the   US Map …  of the  day 10 European model.  We can see the cold air finally moving into Northern Washington State hide a whole Montana North Dakota and Minnesota.

IMAGE  #4   is the chart of the 12z MODEL showing  the   NAO    and EPO   patterns. 

 There are four charts:   the  top   left  one shows the overall NAO.     And you can see that most of the models show this feature becoming consistently but moderately negative over the next 10 to 14 days.  The image on the top right  shows the west based  or GREENLAND  NAO.   Note here that the graphs  are all very close to Neutral…  which is telling us that the Scandinavia block has not reached as far west as Greenland.

The bottom  LEFT  map is the  east based  -NAO   and here we see  a strong   Negative signal which tells us that the Scandinavian ridge   does move    west  over the next 2 weeks.    The Bottom  RIGHT  map   shows the  EPO  phase which finally moves into the positive phase.

LASTLY  image #5  shows the  PNA   trends and all the model data continues to show this feature to be running strongly negative for the next two weeks. 

 SUMMARY:  the pattern is clearly going to start changing over the next 10 days.  But the key here is to recognize that it’s starting to change.    While all this is going on in the northern hemisphere at the high latitudes most of the next 10 days over the central and eastern U.S. will be mild.     For most people today will be seeing the weather pattern and their conditions every day…  and be wondering  “ where is  winter?”….   ” where is the cold air?”…

Assuming that the European   ENSEMBLE means  are correct….  true arctic air  will finally reach western and central Canada   by the 15th…  BUT  not the leading edge of the cold air will Just be  reaching the U.S. Canada border  by NOV 18 .  Assuming all this is correct seasonally cold air will NOT  reached the East Coast before November  20-22.

In addition even though the cold air buildup in western and central and Northern Canada will be impressive over the next 14 days… as  long  as the  PNA   remain   negative…   ( as long as the trough  remains over the  West coast or western   third of the US)     we are talking about a seasonally cold pattern in the U.S.    With a  -PNA there will be no mechanism for the arctic air building up and Western Central Canada to come south.

Now eventually  once the  -PNA   turns neutral and   then positive…  All that cold air building up in central northern and Western Canada will be able to come south.  And that could make for some mighty impressive cold air masses come  DEC  2011…. let me tell you. 

All in all if you like cold weather…  Things are trending your way.  Just remember…  We have a long way to go before we get out of this     super Mild  pattern.

2300  EDT   SATURDAY  NOV  5

CLICK   ON  THE   IMAGES TO SEE    FULL SIZE !!! 

There has been a lot of talk recently from a lot of meteorologists and weather hobbyists about the potential for a pattern change coming up sometime in the middle of November.   This idea has been “fed”    by the last several runs of the operational GFS which has from  time to time over the past 5 to 6 days  which  gone absolutely bat shit crazy – like Michelle Bachman bat shit crazy– in developing a rapid transition to a winter like pattern over the central and eastern portions of the CONUS by the time November 15 rolls around.     The operational GFS and GFS ensemble have… several times   in the past 6 days… developed significant blocking at the high latitudes over Greenland and developed a significant trough over the central / eastern Conus AND ridging in the Jet stream over the West coast.

However it’s not just the operational GFS or the GFS ensemble.    Over the past several days there had been some impressive runs of the European model in detecting some important shifts in some of the high latitude weather patterns.   However the European model because of its overall superiority has  NOT    been developing the extreme cold pattern that the GFS has.    The European model has not developed significant    RIDGE    over the West coast of North America nor has it developed a deep trough over the eastern third of the CONUS. 
   The European model /  european ensembles  the shift towards a colder overall pattern has been much more gradual and realistic.

One of the reasons why energy and grain meteorologists are able to see significant pattern changes coming somewhat sooner than a regular or operational meteorologist can… is because we have look at all portions of the world.    This is especially true for GRAIN meteorologist like yours truly.     Every single day    (except for the weekend)     I spend a lot of time focusing on South America weather…   Australian weather…   the current dry conditions in the wheat areas of the Ukraine and Western Russia… the harvest in Eastern China and conditions in India.     Most meteorologists whether its TV or NWS do not and this is critical IF   you are trying to    see what is going to happen day 10… day  15….   or day 20. That is why most forecasters don’t try and make a forecast past Day 7.

Some people were born to play baseball. Some people were born to complain. I was born to forecast.

Let’s take a look at the Maps!

This first image shows the current overall pattern across the entire northern hemisphere at 500 MB. And there are several important features we can talk about

I have highlighted the important features by NUMBERS in order for you to be able to follow which particular features I am focusing on …and also so that you can begin to see how weather patterns are all interconnected and related.    By getting a better handle about how things are developing hemispherically a good forecast has a better idea of what if a model solutuon at day 8 or day 12 is reasonable or well… bullshit.

The MOST important feature here is the PV — POLAR VORTEX which is centered the ASIAN side of the arctic circle. This Position ois the KISS OF DEATH for anyone wanting cold weather in the eastern or central Conus.    ANY Model solution that shows a cold pattern developing over the central and eastern CONUS cannot possibily be    “valid”   as long as the main PV is over on the Siberian side of the Arctic circle.   Keep that in Mind.

…and Yes this is WHY the AO — the Arctic Osciallation has been so strongly positive.

FEATURE #1   Over the past week has been a deep and persistent trough in the jet stream over the northeast Atlantic Ocean which has been battering Western Europe with a series of powerful Lows.    Some of the deep Low pressures between Iceland and Ireland have reached as low as 950 MB.    The trough has become massive over the past week and has extended as far south as northeastern Spain and Portugal.

This is major trough is part of the VERY strong +NAO

FEATURE #2…   Remembering your basic physics… for   every action  there is  as an equal and opposite reaction…   the atmosphere responses  to this deep trough over the northeastern Atlantic…   by countering it   with  an  equally strong and large Ridge which has covered much of Eastern Europe the Ukraine Belarus and Western Russia.     Last week it was reported that over 20% of the winter wheat crop in the Ukraine has to be implanted the cause of excess of the dry conditions– which is due to the persistent Ridge in the Jet stream.

In addition to take a look at the strong TROUGH over the central Russia… extending from the Urals into the Caspian Sea. This trough is the opposite of the ” cahirs connection” … a feature which JB has mentioned many times.   Briefly if you are not familiar with this particular feature the argument goes that when there is a Ridge developing over Central Russia from the Caspian Sea north towards the Urals it leads to a +PNA pattern over the N. America 7-10 day later.

FEATURE #3   is enhanced Pacific Jet stream that is caused by a ridge over the north Pacific ocean. This ridge is pressing up against the large Polar Vortex that is Just North of Siberia.    This is causing the Pacific Jet to get ” squeezed”    or compressed so its velocities are enhanced.    This give the Pac jet a lot more power… which leads to

FEATURE #4…   the deep persistent trough over the West coast. This trough combined with the very strongly +NAO means a ridge over the eastern US and eastern Canada and NO “significant” injections of cold air    (just the occasional cold air blast for a day or so).

By day 10 there are significant changes developing over all of the northern hemisphere.

This   IMAGE  compares the day 9 European   ( LEFT side)   and the day 9 GFS   ( RIGHT side). To begin with the deep persistent trough in the northeast  Atlantic extending from Iceland and down towards Portugal has weakened significantly.    Both models move is trough back out further from Western Europe into the eastern / central N. Atlantic.

In response (#2 )   the persistent large ridge over the Ukraine and Western Russia is able to slide west into Central Western Europe.    This in turn causes the ridge to build towards Iceland & eastern Greenland.

However as you can clearly see both models continue  the strong positive height anomaly – RIDGE -over the central portions of the northern Pacific (#3). 

As a result this strong Pacific jet stream continues to really fire across the northern Pacific through the gulf Alaska and down into the west coast of North America and especially of the CONUS. (#4) . 

This is telling me that the persistent trough over the Western North America is  NOT   about to shift or change in any significant way through the middle of the month.   In order to get deeper western trough to go away… and to get a Ridge over western North America… the Pacific jet stream has got to relax… and that in turn means the N Pacific Ridge has got to breakdown OR the polar vortex over the Siberian side of the arctic circle has got to change.

#5… Both models   show  t the PV is   going to be moving or shifting position by day 9… from the n. Siberian coasts along the Arctic circle… then moving towards far northwest portions of North America.   In fact some of the model show the PV splitting into two features with one remaining over central Siberia and the other one moving towards the north slopes of Alaska.

We can clearly see this on the enlarged  European map at DAY 10.

Not surprisingly if we look at the TRENDS with the AO and the NAO we see that most of the data showing an increasingly negative values into both of these features.

The 12z operational GFS showed the AO staying quite positive right through the next two weeks but the GFS ensemble and the European and European ensembles showed increasingly negative trend.   This should be a warning sign that along as the pattern is in transition … whatever the GFS happens to be showing past day 7… it should be regarded as essentially worthless until the new pattern finally reveals itself.

The NAO TRENDS… are even better.   All four  plots    show    that the NAO is going to turn negative and the European models are specially bullish on this. In fact I have seen the individual European ensemble maps in the 11-15 day . I cannot post them but I can tell you that they are quite impressive with the developing Heights and ridging over Greenland building towards eastern Canada.

Now that being said… this is where weather hobbyists and weenies often miss the boat.   Right now we are in a very bad pattern for any sort of winter weather. I think I had made very clear about all the things which are hostile with regard to getting any sort of sustained cold pattern over any portion of North America Eastern Rockies.

• The PV is on the wrong side of the world.
• The Pacific jet is howling and we have a deep persistent trough on the West Coast.
• The NAO is extremely positive. 
• The lack of any sustained large cold air masses over the entire southern half of Canada!!!
• There is no way of getting any sort of this severe cold which is developing in Siberia over into North America in any way shape or form.

Just because the AO and NAO are both going to turn negative NEXT WEEK…. it does not mean that it is going to be snowing at your house by November 15.     All it means is that the  OVERALL    pattern is going to turn somewhat more favorable  by the Middle of  the month.    In other words IF  you like    cold and wintry weather …  the pattern shifts from unbelievably crappie     to a pattern which does not totally suck moose.

We still have a long way to go and we still have to get that the persistent trough along the West Coast to change   . The AO and NAO can be negative for a long while before the pattern begins to shift in the northern Pacific.    EVENTUALLY …If we do get the PV towards north central Canada or Hudson’s Bay that would be an impact the pattern over the north Pacific area and allow the Pacific jet to relax and the deep trough over the West Coast to go away.

But we are still talking a few weeks here folks.  He ware  headed  in the right direction    but there are a LOT of  things  to  FIX  here … and   its   going to  take a while.