A severe thunderstorm watch is in effect for the Poconos, Catskills, Delaware River Valley, and New Jersey coast as a surface trough of low-pressure approaches the region ahead of the main cold front. This trough supports lines of showers and thunderstorms capable of reaching severe levels. The vertical wind shear is present but not very strong, so while I can’t rule out a rouge isolated tornado, the primary threat through this evening will be hail, wind gusts over 55 mph, vivid frequent lightning, and torrential downpours.
There will be a high threat of flash flooding and urban flooding due to the slow-moving nature of these thunderstorms, which is a threat for the entire region from eastern Pennsylvania to eastern Connecticut and Long Island. In some locations in Connecticut, over 5″ of rain have been reported, and similar rainfall amounts are possible with a few of these thunderstorms. Use extreme caution in heavy rainfall, and do not drive in submerged roadways as they are often deeper than you think.