The January thaw is over and it’s back to the cold pattern for  from the Northern Plains to Southeast thanks to rebuilding of high pressure northwards. In the last 7 days, troughiness has returned to Alaska and so the recent cool shots has been a mix of Pacific and Arctic air but that’s about to change.

Thank or blame the abnormally warm waters over the Gulf of Alaska as well as other aspects for the much colder winter for the US compared to the last 2 years. Exceptionally dry conditions over California up into the Pacific Northwest is helping boosts those positives but the warm water is really doing it’s dirty work for sure.

(TOP Image credit: Pierre Rohel  @p_rohel)

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So, it’s cold now across the Midwest and East but it’s more typical cold for mid-January. A series of clippers riding the northwest flow from the Yukon is not just pushing cold air back south but their laying down the snow cover again, setting the stage for MUCH colder air next week but what follows next week, may be of historic proportion, either matching or exceeding the depths of cold witnessed during the opening 7 days of the month.

The snow can be laid down in two ways this upcoming 7-10 days. Via 1) clippers 2) systems which form along trough base with low pressure developing at the coast with Atlantic feedback which runs up the coast. Note the warm waters immediately off the coast in the above chart.

Here’s the GFS snow chart through the next 10 days.

ECMWF 10 day

This upcoming 2-3 week period looks to be coldest of the winter with three waves of cold. The current one like I say is ‘typical’ brand cold, next week will be considerably colder with NO Pacific mixing and so highs may stay BELOW 0 mid next week in Chicago and Detroit with a possible run at ZERO in NYC, Philly and if there’s snow on the ground, DC also. Then the mother of all cold waves drops down on the backside of yet another clipper week 3 or between 22-30th.

Check out the GFS Ensemble 7 day MEAN 500mb height anomalies.

Front running 7 days.

Note the ridge poking up into Alaska and the arctic.

7-14 day (next week) shows stronger positive over AK, negative over Great Lakes.

By day 9-16

Note the blocking over the top of Arctic Canada and hooking up of the AK-Greenland high with potential linking with central Atlantic high too. This would signify a more locked in cold trough over the eastern US as we head into February. Up till now, each cold shot has managed to escape out into the Atlantic without any blocking. The NAO appears to go negative week 2-3.

Here’s the GFS ensemble temperature anomalies or departures through the upcoming 16 day period. Note the departures get colder through the period. VERY impressive given that these are 7-day MEANS.

Week 1

Week 2

Day 9-16

Here’s a closer up look at just how cold the troughs get at the 850mb level week 2 and 3.

24 hrs (tomorrow)

120 hrs (next Wed) MUCH COLDER!

The mother of all cold blasts…

240 hrs (day 10)

Here’s the CFSv2 week 1-2 temps.

Week 3-4

ECMWF is just as extreme and persistent but still room of change and weakening of the cold’s intensity. However, the overall pattern is very conducive for this extreme solution given the tanking again of the Arctic Oscillation and the northward push of the AK ridge with strong +PNA.

As for February overall, it’s looking cold, especially with the potentially development of a Greenland block which would hold the eastern trough in place. See the video for details on that.

Here’s the charts shown to you in the video.

700mb height anomalies for February show blocking.

As a result, here’s the surface temps. VERY chilly looking for the US.

Close up of US.

Here’s the CFSv2 attempting to hooking up the Greenland and central Atlantic ridge which could lock in eastern US cold next month.

SEE VIDEO for further explanation!

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Tags: arctic oscillation, arctic outbreak, February forecast, north atlantic oscillation, polar stratosphere, polar vortex, snow, stratospheric warming, US Cold