Around here, the prevailing direction for rain to travel is from west to east (or some variant of west to some variant of east). It's not often you get east to west traversing showers but you are getting them today and tonight as an upper low is pivoting towards us. Showers have been pushing off of the Atlantic, moving northwest and then west-northwest as they get into South Central Pennsylvania. As of 4:30 PM, radar looks like a scattered hodge podge of precipitation as there are a number of showers around, mostly to the south and west of Philadelphia, with fewer showers in number as one tracks north and northeast.
These showers are more numerous in number as one tracks south and southwest, with a larger number of showers down near Washington, across Northern Virginia, and offshore of the Virginia Capes and Ocean City, Maryland area. That area of heavier rain and thunder in the Atlantic is modeled to push towards our region later tonight, with high resolution versions of the NAM suggesting that the area of heavy rain and thunder currently in the Atlantic will push through our region after 10 or 11 PM this evening.
Some one inch rainfall totals are possible in spots, particularly where the heaviest bands of precipitation travel -- best chances of this are west of the city and also north late tonight. Some of the showers and storms as they move through overnight and tomorrow could produce localized downpours as they move through.
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