Southern New England Derecho

Southern New England Derecho
Presented by Hayden Frank

1:50 p.m. – 2:10 p.m.

A rare high-end Severe Weather Event in the form of a Derecho struck southern New England on October 7, 2020. Widespread damaging wind gusts of 60 mph with embedded gusts to Hurricane Force occurred. This Derecho impacted central and eastern New York, Massachusetts as well as portions of southern New Hampshire. The Storm Prediction Center determined that the length of the widespread nature of the damage which included several higher-end gusts qualified for a Serial Derecho. At one point, there were nearly one-quarter of a million people without power in Massachusetts alone.

In this presentation, we examine the meteorology behind this highly unusual Derecho across southern New England. Both the upper level and surface features will be utilized in this presentation. This will include how very strong jet dynamics were able to compensate for the limited instability. Despite the limited instability, steep mid-level lapse rates were present along with ample 0-3 KM Cape. These two characteristics are typical for high-end severe weather events.