Image: ECMWF/Pivotal
January 20, 2021
❄ Pattern amplification starting to work into the USA but models still struggling...
The pattern change mentioned last week has started. The first piece of this puzzle started late last week. A couple glancing shots came over the last few days keeping things colder with rounds of snow. A brief surge tomorrow, Thursday, sets the stage for another cold shot to push into the central and eastern USA. Each storm will help amplify the pattern further.

The key to sustain cold air for longer periods of time will be the tropical connection. Storms that feed on this energy will lead to deeper, stronger, and colder implications to the sensible weather. The next big piece should come Sunday into Monday.

Image: ECMWF/Pivotal
January 20, 2021
Operational models have struggled mightily because they mishandle the southeast ridge and the increasing depth of the polar vortex. The snow map image above is not to show snowfall totals, relative to amounts, but to the southward progression. I contend that each storm will pull colder air south to a point, shunting the southeast ridge that tries to make the eastern USA remain in a blowtorch, warm pattern. Let's see how things keep evolving.

⛅ Forecast provided by: Meteorologist Joshua Ketchen

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