In my search for some winter weather a tweet by Amy H Butler about dynamic final warmings piqued my interest.
According to the atmospheric scientist a winter where there was no major disruptions of the polar vortex (SSW) we are more likely to see a dynamic early final warming. A table published by Wiley shows the final warming dates.
So what could this mean for the weather in the London area? Considering all the above years with no SSW gives an average date of April 19th for a dynamic final warming.
I then looked at the TMax anomaly for those years for 60 days following a DFW and came up with the following graph.
The results suggest temperatures in April will be heading down in the final week for a cold end. The average to cool theme continues into May before temperatures lift in the final week for a warm end, with anomalies up to 5C above average. June, however, looks shocking with temperatures nearly 6C below average by the 16th.
This winter has so far been very similar in type to 1990. The dynamic final warming that year was among the latest in the list and led to a cool and dull June with anomalies in the second week nearly 7C below average!