Verification Discussion (10/30/14)

 

Stratospheric A Event (forecasted):

A cold air event was observed around the 11th of October for both the North American and Eurasian continents. The cold air event was preceded by a significant increase of stratospheric mass transport into the polar circle with a peak rate of 600 million tons per day, nearly three times as much as that just a few days prior. The timing of the increase of stratospheric mass transport into the polar circle is in good agreement with the predicted Stratospheric A event made since September 22, except the actual event took place 2-3 days earlier. Our prediction of a cold air event around this time period was predicated on the predictability of the increase of stratospheric mass transport into the polar circle. Thus, we were able to predict this cold air event weeks in advance.

 

Cold Air Event 2 (not forecasted):

An unforeseen cold air event occurred around the 21st of October for both the North American and Eurasian continents. Observations indicate that the cold air event was in fact preceded by an increase in stratospheric mass transport into the polar circle. This increase, however, was not significant enough to be confidently noticed in the forecast. Therefore no cold air event was predicted.

 

Stratospheric B Event (forecasted):

Since 9/22, the forecast has been calling for a cold air event around the week of Halloween (Oct. 31st). Observations have corroborated this prediction, as a significant cold air event is occurring in the Eurasian continent with approximately 65% of the continent experiencing cold anomalies. The North American continent is also experiencing a cold air event, though less extensive. The current cold air event was preceded by an increase in stratospheric mass transport into the polar circle matching the Stratospheric B event prediction.