Verification Discussion (11/21/14)

 

Stratospheric B Event

(first forecasted on 9/29/14):

The stratospheric event B was a three-peak event, which as predicted occurred around the week of Halloween. No major cold air outbreak was associated with the first peak. The second and third peaks preceded an extended cold air outbreak event with two peaks of maximum cold area, which occurred over both the Eurasian and North American continents from approximately 10/31-11/05.

 

Stratospheric C Event

(first forecasted on 10/6/14):

Stratospheric event C, which took place between 11/9-11/11, was forecasted to occur between11/12 and 11/15 on 10/6/2014 and revised to occur between 11/07 and 11/11 on 10/21. Observations show a cold air outbreak event over North American continent starting a few day before the first peak of the stratospheric C event. The second peak preceded long lasting cold air outbreak events that started on 11/11 over both the Eurasian and North American continents.

 

Stratospheric C1 Event

(mentioned on 10/6 but first officially forecasted on 11/6/14):

Currently observations indicate an anomalously strong stratospheric event is occurring (first peak had intensity of 700 billion tons per day of air mass transport into the polar stratosphere and the second peak was as large as 1 trillion tons per day). This round of large increase of stratospheric mass transport matches the predicted stratospheric C1 event.  The first peak (11/17) of stratospheric C1 event was just a day after a peak in the cold area index over both North America and Eurasia. The back-to-back two stratospheric events (C and C1) within a week made both continents suffering from a prolonging of cold temperatures in the past week and the week after, particularly in the North American continent, where currently about 95% of the continent is experiencing colder than normal temperatures.