7:00 AM | ****Heavy rain event from later today into Friday in much of the eastern US...localized flash flooding a concern****
Paul Dorian
6-Day forecast for the Philadelphia, PA metro region
Today
Cloudy this morning with an occasional shower possible, steadier rain develops around mid-afternoon with a late day thunderstorm or two possible, some of the rain will be heavy at times late in the day, watch for localized flooding, becoming very windy with gusts past 40 mph, mild, highs in the mid 60’s
Tonight
Periods of rain, maybe a thunderstorm or two, some of the rain will be heavy at times, windy, mild, lows in the low-to-mid 50’s
Friday
Mainly cloudy, breezy, mild, occasional showers are likely, maybe a thunderstorm, mid 60’s for afternoon highs
Friday Night
Mainly cloudy, cooler, a few residual showers are possible, maybe a thunderstorm, near 50 degrees for late night lows
Saturday
Early clouds and maybe a shower give way to mainly sunny skies, breezy, milder, mid 60’s
Sunday
Increasing clouds, warmer, chance of showers late in the day and at night, near 70 degrees
Monday
Partly sunny, mild, chance of showers, near 70 degrees
Tuesday
Mainly sunny, cooler, near 60 degrees
Discussion
A north-to-south oriented surface cold frontal system that trails low pressure over the Great Lakes is inching its way towards the east coast and the atmosphere will moisten up significantly ahead it with an influx of tropical air from the Gulf of Mexico, SW Atlantic, and Caribbean Sea. This influx of tropical air will set the stage for excessive rainfall later today and tonight in much of the eastern US extending from the Carolinas to New York State. In fact, given the very slow movement of the frontal system and the high precipitable water amounts expected, total rainfall amounts could end up between 1.5 and 3 inches and flash flooding will become an increasing concern given the already saturated grounds. The upper-level energy supporting the low pressure will move over the Mid-Atlantic region on Friday generating additional showers and maybe a thunderstorm or two. The weekend should start off on a decent note with some sunshine on Saturday and milder conditions after possible early morning lingering clouds. Another system, however, is likely to push more showers into the region by later Sunday afternoon or Sunday evening.
Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com