1000 EDT 14 JULY
The Wednesday 0z operational European model is showing a significantly different pattern than the 0z GFS and the 0z CMC. These models continue to develop a pretty powerful dome over the Plains and the Midwest in the 6-10 day. To the European begins to form a dome during this time frame.
The Canadian however develops a pretty serious trough over the northeast which keeps the dome centered over the Mississippi Valley of the plains states. That trough appears to be…according to the 0z Wed Canadian …. strong enough to keep most of the East coast (including Virginia) in a much cooler weather pattern and this would also affect the Ohio Valley as well.
The GFS shoves the dome in the Midwest SOUTH as the Model develops a weak cold front over the Great Lakes and Northern New England. The front presses south JULY 24-25-26 and brings about some showers and thunderstorms to the great lakes and the northeast. At this point it is impossible to say if the storms will reach Virginia. The Models keep the Dome over the Deep South … whiich again IF correct would bring in several days of U 90s and L 100s degree temperature readings.
The 0z Wednesday Europran continues to show the dome further south and any of the models. And because of the model has the dome so far to the south a pretty significant cold front moves into the upper plains and a good portion of the Midwest July 24-25 and into the Northeast July 26-27. The 0z Euro ensembles are not nearly as far south as the operational run.
No matter which of these possible solutions is correct the all show that the dome is either going to come due east from the Midwest region into the Ohio Valley and the Middle Atlantic states… or the dome gets shoved south … then comes east. There are of these possible so areas looks like a very hot last 10 days of July for the commonwealth…. a 3rd round of temps near or above 100 degrees seems a good bet.
1100 EDT JULY 12
As I am sure most of you know it’s been a very hot summer throughout the commonwealth as well as the Middle Atlantic states and in fact the entire eastern third of the Conus. June 2010 was the hottest or one of the hottest June months on record . Minor drought conditions had begun to develop across the commonwealth and if the current hot and fairly dry pattern continues then it looks like the drought conditions will probably worsen as we go through the second half for July and into August .
The weather models over the weekend and early this month morning continue to show the developing potential of a major heat dome for the Midwest and the Plains states developing in the 6 to 10 day period. All the models are showing this dome and given that we are now in any rapidly developing an increasing LA NINA pattern this sort of pattern development is a supported by the overall seasonal trend .
But beyond that this new pattern has significant implications for Virginia and the the entire Middle Atlantic region.
This looks like a warm weekend pretty typical for what will see in mid July with temperatures likely range in the low to mid 90s across the entire commonwealth. A cold front attached to a fairly strong area of Low-pressure and Eastern Canada will move through the big cities of the East coast Saturday night or Sunday. This front should be strong enough to provide significant showers and thunderstorms to much of the commonwealth as well as the big cities of I -95.
This cold front will be followed by another fairly vigorous cold front moving through the NE Conus JULY 20-21. It is during this period that the heat dome over the southwest states will begin to slide east expanding into the Central and Lower Plains and into the Midwest BY DAY 9-10…. JULY 21-22.
The entire forecast for this weekend for Virginia… as well as MD DE WVA and NC…. depends on the development and the position of this massive Dome in the Jet stream that all of the weather models are currently developing over the Plains and the Midwest after July 20. The day 10 ECMWF 0z run…. has this Dome centered over the Midwest and the Delta. There is a weak trough off the New England Coast and the model makes it clear that the dome is rapidly building into Western Virginia western NC and into the Lower Ohio valley.
If this sceanrio is right VA could see its 3rd round of 100+ degree temps starting in this weekend . The heat may Not make it past DCA or BWI as the models all keep a weak trough over New England.
This would bring back eight another significant interval of 100° plus temperatures