Weekly Highlights

(11/21/2014  − 11/25/2014)

·       STRAT_D is expected to peak around November 30, a few days earlier than 12/03 - 12/07 that we first forecasted on October 28.  The cold air outbreaks associated STRAT_D are expected to be not as strong as the STRAT_C1 cold-air waves.

·       Between STRAT_D and STRAT_E, we will have event STRAT_D1. This event is forecasted to peak first around December 16, followed by a second peak around December 20-22. STRAT_D will bring cold air outbreaks during the week between December 18-24, leading to another round of wintery precipitation such as snow, sleet, and freezing rain across both the North American and Eurasian Continents. This would affect pre-holiday travelers greatly.

·       The STRAT_E event is expected to occur from December 31, 2014 to January 3, 2015. Major cold air outbreaks are expected in the week after the New Year’s Day, which would impact post-holiday travelers because of its large impact area (continental scale).

Follow-up of Forecasts Made before This Week:

·       STRAT_D, first forecasted on October 28, is expected to peak around November 30. The cold air outbreak associated with this STRAT event is expected to be weaker than those associated with STRAT_C and STRAT_C1.

·       STRAT_E event, first forecasted on November 20 to occur in the last week of December, is expected to take place between 12/31/2014 and 01/03/2015.  Major cold air outbreaks are expected in the week after the New Year’s Day. This round of cold air outbreak events will bring in below normal temperatures for much of the area within the middle latitudes. 

New Forecasts made on November 25, 2014:

·       In this week, we forecast a new event, STRAT_D1, to peak first around December 16 followed by a second peak around December 20-22. The STRAT_D1 event is part of the D-series of STRAT events that was first forecasted on October 28, but later canceled in our forecasts made on November 6. This event is forecasted to transport more than 700 billion tons per day into the polar stratosphere at its peak time. Therefore, this will bring a rush of cold air into much of the mid-latitudes leading to another round of cold-air waves to occur December 18-24, which can heavily impact early travel for the holidays. Another round of wintery precipitation is likely to result because of this rush of cold air, such as snow, sleet, and freezing rain across both the North American and Eurasian Continents.