1:30 PM | **Heavy rain in the Mid-Atlantic region on Thursday and potential widespread severe weather event**
Ingredients are coming together for a possible large outbreak of severe thunderstorms in the Mid-Atlantic region on Thursday capable of producing damaging wind gusts, hail, torrential rains and even isolated tornadoes. The greatest chance for severe weather in the Mid-Atlantic region will likely be in the region from central New Jersey and east-central Pennsylvania southward to Virginia, Maryland and the Delmarva Peninsula which would include the metro regions of Philly, Baltimore and DC. There can be some shower and thunderstorm activity as early as late tonight in the Mid-Atlantic region, but the main action will occur on Thursday and Thursday night.
The severe weather ingredients coming together for this upcoming event include the following:
1) An intensifying and unusually strong low pressure system for this time of year (model forecast map on Facebook page)
2) Yet another unusual deep and cold upper level (500 mb) trough of low pressure
3) A strong low-level jet (850 mb) with 50 knot winds
4) An unusually strong high-level (250 mb) jet streak with 100 knot winds
5) Strong wind shear supportive of updraft rotation
Heavy rain on the order of 1-3 inches will raise the chances for flash flooding on Thursday as grounds are very saturated due to recent heavy rains throughout the region. Since the remains of Tropical Storm Andrea raced up the east coast last Friday, much of the Mid-Atlantic region has received more than 6 inches of accumulated rainfall. The strong low pressure system will head northeast along the New England coastline late tomorrow night into early Friday – much like a wintertime nor’easter. As a result, that part of the Northeast US could get “non-thunderstorm” winds of 50 knots or higher causing scattered power outages particularly in coastal New England and eastern Long Island.