Major Flip-Flop on the ECMWF tonight ...

[Stormsfury]

Last night, the EC depicted a cutoff low in the SW US for the 3 day averages for days 8-10 ... tonight, quite the opposite ... subtropical ridging in the SW with a southern stream trough over the Southeast for the 3 day average ...

ECMWF Days 8-10 3 day average

According to the EURO tonight, a polar vortex is on the move to our side of the pole (very slowly) and situates itself over AK with some very cold termperatures by Day 7 ... and continuing into the 10 day range ...

3 Day average days 8-10 Northern Hemisphere

But as for any sustained cold air in the US for the next 10 days ... highly doubt it ... The flow across the US is about as flat and zonal as it could be ...

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SF

[RNS]

the EC lost the cutoff...but there are some critical things here...

Slight troughing is noted near japan, with cutoff low pressure located just to the east...this cutoff argues to pump the ridge overtop of the low, and amplify the trough in the Gulf of Alaska. Secondly we have the trough off the west coast of north america which says that the ridging should be present in the central part of the country as the EC would indicate.

next we have a very deep trough in spain, with a cutoff developing at the base of the trough. given the goings on in the far east and the pacific, this too will likely cutoff. therefore, the EC is probably incorrect with regard to the amplitude of the trough in the eastern part of the country. one would think based on the fact that the trough is deep in western europe, and low pressure at H5 is beginning to cutoff near the base of that trough that the EC is underdoing the amplitude of the trough, missing the fact that a cutoff will most likely try to develop, and the fact that heights should be lower within the EUS trough as a whole (indicative of more cold air).

So on second thought the energy the EC was holding back the day before in the southwest may be what is at the base of the H5 trough on the day 8 to 10 average, tonight.

the flow overall is one which IMO favors a tendency for stronger amplification during this period, and one which is less zonal than wha tthe model predicts. howeve that said, with all these cutoffs around...the EC/s zonal tendency may not be off target...as when one has a pattern that is anchored by cutoff low prerssure centers, wavelengths tend to be borader...arguing against the ideas established above.

what i do think we can conclude is that this is the BEGINNING of the pattern change, even if the wavelengths are broader across north america (indicating a more zonal pattern - not the most favorable for cold air, but not as unfavorable as a pattern which is truly zonal), the slow retrogression of the ridge toward the southwest, movement of the vortex out of its position along the north shore of AK, and the changes in the atlantic and pacific SSTA configurations support this trend.

[RNS]

we will also have to see what the ridge wants to do as it progresses toward the caspain...last nights run had the ridge right near the critical 70E position, tonight it is much further west, so we will see.

[wx247]

Our local NWS has been flip flopping the last few days as well with the extended. Last night they had snow for us and temps in the lower 30's on Sunday. Now it is forecasted to be sunny and near 60. What gives!!!