Showers and storms are slowly approaching from the west. A line is situated from the Poconos southwest to Harrisburg, with individual storms moving northeast as the line is pushing east. None of these storms as of now are severe although a few gusty rumbles of thunder are possible tonight as the line moves in after 6 PM in the west, after 7 PM locally. Could there be a severe warning that crops up from this? Yeah, but odds don't really favor it though.
The NAM computer model suggests that the line of thunder devolves a bit -- becoming a line of showers and perhaps some thunder embedded within it later tonight as it crosses the region. Occasionally heavier showers will ride northeast along the front as it pushes east. The NAM at 2 AM (below) suggests showers overhead except at the Shore -- and yeah, the Shore folks should be in for a nice night although it will be warm. That said, Saturday will deal with showers there longer than in Reading, which should be shower-free by daybreak as the front nudges through slowly.
Modeling does suggest some heavier rainfall totals in areas with the heaviest of showers -- but most spots might see a half inch or less of rain from the city on south. North of the city seems to be where the best potential for heavier showers resides and some spots could pick up over an inch of rain overnight, especially from Reading to Pottstown to Doylestown to Allentown. That general area is highlighted by the NAM as being prone to potentially heavier rainfall overnight.
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