Seasonably warm to hot weather will prevail across the Northeast during the upcoming week as the main branch of the jet stream remains across southern Canada. Meanwhile, the blistering hot spell that brought all-time record heat to a wide area from the Tennessee Valley to the Southeast/ southern Mid-Atlantic will slowly fade as the large ridge of high pressure in the upper atmosphere (that prompted the extreme heat) weakens…which will allow for cooling afternoon thunderstorms to erupt over the heat-stricken region.
The Northeast will lie close enough to the main branch of the jet stream this week to allow for some weak frontal passages each of which will increase the opportunity for showers and thunderstorms at times. These “times” are noted in the details below. Unfortunately, it looks like the 4th of July holiday will be one of those times for heightened thunderstorm risk (due to a shortwave/jet-stream disturbance passing overhead which will drag a weak cold frontal boundary through the Northeast States). Nevertheless, despite the heightened chance for thunderstorms, much of the day on the 4th should be dry.