Weekly Highlights:Two more rounds of cold air outbreaks on their ways and possible wintery precipitation over the US around the April fools day
(03/13/2015 − 03/20/2015)
As forecasted originally to occur between 03/12-03/17 on 02/12, the mean peak of STRAT_J occurred on 03/16 with intensity of 0.9 trillion tons per day of air transported into the polar stratosphere. Cold air outbreaks took place a few days after the peak day, resulting in about 60% of the area reporting below-normal temperatures over the US, and 50% of area over Eurasia. Wintery precipitation has been pounding the east coast area of US since yesterday, as headlined by the Weather Channel “Winter Storm Ultima Brings Snow to the Northeast as Spring Arrives”, and also discussed in our weekly highlight of our last week’s forecast “Winter is not over yet”.
Originally forecasted on 02/18, STRAT_K is expected to occur within the last few days of March and the first few days of April. The duration of this event will last 4-7 days because of the various peaks expected to occur during the passing of this system. Below-normal temperatures will return for both North America and Eurasia. Another round of wintery precipitation events are likely to occur over the US.
This week, we are forecasting STRAT_L to occur in the week around April 16-22. Although it is unlikely that STRAT_L will bring a new round of wintery precipitation events, we are expecting up to 60% of area over North America and Eurasian to report below-normal temperatures. STRAT_L is very likely to be the last STRAT event in the winter of 2014-15.
STRAT_J, K, and L events will make the spring of 2015 be a cold spring
Forecasts Made on March 20, 2015
Follow up on Forecast Made in Previous Weeks:
· STRAT_J has arrived on time, resulting in about 60% of the area reporting below-normal temperatures over the US and 50% of area over Eurasia. Wintery precipitation has been pounding the east coast area of US since last night.
· STRAT_K is still looking to occur within the last few days of March and first few days of April. We are expecting continental scale cold air outbreaks over both North America and Eurasia. Since STRAT_K is a strong event, it will particularly affect the US. We are calling for another round of winter-like weather for North America.
New Forecasts Made on March 20, 2015
· This week, we are forecasting STRAT_L to occur around April 16-22. We are expecting up to 60% of area over North America and Eurasian to report below-normal temperatures. This event is very likely the last major cold air outbreak event for the winter season of 2014-15.