Thursday, October 17, 2013

Intense Cold Snap Here to Stay

A cold snap which has just begun in the Plains and Midwest is here to stay, and will expand east in the process.

The atmospheric pattern has changed in the last couple of days, with ridging starting to build over the Gulf of Alaska and western coast of North America. This has started to lead to troughing/a colder weather pattern in the Central US, and this will intensify in the next several days, with the 10 day forecast above showing this pattern continue.

GFS ensemble temperature forecasts show this cold trend continuing and intensifying in the next several days, before the cold air mass slowly drifts east and weakens with time. I'm monitoring the GFS ensembles for moving the cold air out too quickly, as a recurving typhoon in the short and long range should keep at least a cool air mass across portions of the nation in the long-long range (i.e. 20-25 days).

This actually does have implications for the coming winter, and I will go in-depth with it when the Final 2013-2014 Winter Forecast is released next week, possibly on Thursday (one week from today).