HARRISBURG, PENNSYLVANIA — A rainy Sunday is ahead for Pennsylvania. A blend of models showcasing potential rainfall amounts for Sunday, September 20, valid through 5:00 a.m. EDT Monday, September 21, shows rain entering the state late tonight into tomorrow morning and lingering for the majority of the day, according to AguaceroWX. A general 0.50 to 1.00 inch of rain is expected statewide, with localized amounts of 1 to 2 inches, and forecasters warn residents should be prepared to dodge raindrops tomorrow with limited dry time throughout the day.
Rain Arrives Late Tonight Into Tomorrow Morning Statewide
If you’re anywhere in Pennsylvania, plan on rain moving in overnight and continuing through most of Sunday. Unlike a quick-hitting system that clears out by midday, this rain event is forecast to linger for the majority of the day, meaning outdoor plans across the state should build in the expectation of scattered showers persisting well into the afternoon and evening rather than a brief morning soaking followed by clearing skies.
Central PA From Williamsport to Pottsville Sees the Heaviest Totals
The heaviest rainfall on tomorrow’s forecast map concentrates across Central Pennsylvania, with Williamsport forecast for 1.21 inches, Lock Haven at 1.19 inches and Pottsville topping the list at 1.36 inches. Nearby Bloomsburg, Selinsgrove and Sunbury all show similar totals in the 1.06 to 1.14 inch range. If you’re anywhere across this corridor, from State College through Williamsport and into Pottsville, expect this to be one of the wetter pockets of the entire state tomorrow.
State College and Centre County Face a Wet Day With Convective Storms Possible
State College itself is forecast for 0.83 inches, with nearby Bellefonte at 0.78 inches and Philipsburg slightly lower at 0.75 inches. Because State College sits close to the I-80 corridor, forecasters specifically flagged this general area as one where thunderstorms may develop, giving rainfall here a more convective nature. That means totals could vary noticeably from one neighborhood to the next depending on exactly where a stronger cell happens to set up.
South of I-80, Uneven Rainfall From Developing Thunderstorms Is Likely
Forecasters were direct that there will be a convective nature to some of tomorrow’s rainfall, especially south of I-80, as thunderstorms may develop and produce uneven totals from location to location. If you’re anywhere south of that corridor, including Harrisburg, Lebanon, Reading and Lancaster, don’t be surprised if your yard sees meaningfully more or less rain than a neighboring town just a few miles away; that’s the nature of convective rainfall compared to steady, widespread showers.
Wilkes-Barre, Scranton and Northeast PA See Solid Totals Too
Across Northeastern Pennsylvania, Wilkes-Barre is forecast for 0.85 inches, with Hazleton at 0.85 inches and Moscow slightly higher at 1.09 inches. Farther north, Montrose and Binghamton-adjacent areas near Elmira show some of the highest totals in the entire northern tier, with Binghamton itself forecast at 1.13 inches. If you’re anywhere across this stretch of the Poconos and northeastern counties, plan on a genuinely soggy Sunday.
Erie and Northwest PA See Lighter, More Scattered Rainfall
Out in Erie and the surrounding northwest corner of the state, totals run noticeably lighter, with Erie forecast for just 0.45 inches and nearby Edinboro at 0.31 inches. If you’re in this part of Pennsylvania, tomorrow’s rain event should feel less impactful than what’s expected across the central and northeastern parts of the state, though scattered showers are still likely throughout the day.
Harrisburg, York and South Central PA See More Modest Totals
Closer to the Maryland border, Harrisburg is forecast for 0.66 inches, with York trending lighter at 0.39 inches and Gettysburg at just 0.24 inches. Communities along this southern tier, including Chambersburg and Carlisle, should see a real but comparatively lighter rain event than the heavier totals expected farther north across the State College and Williamsport corridor.
Philadelphia and the Southeast Corner See the Lightest Totals in the State
The lightest rainfall totals anywhere in Pennsylvania are forecast across the far southeastern corner near Philadelphia, with spots like West Chester coming in around 0.20 inches and areas near the New Jersey border even lower. If you’re in the Philadelphia suburbs, tomorrow’s rain should be the least disruptive of anywhere in the state, though scattered showers moving through from the northwest could still bring brief downpours during parts of the day.
Pittsburgh and Southwestern PA Face a Solid but Moderate Rain Event
Out west, Pittsburgh and its suburbs, including Greensburg at 0.66 inches and Latrobe at 0.93 inches, fall into a moderate rainfall category, generally in the 0.5 to 0.9 inch range. If you’re in Southwestern Pennsylvania, expect a steady, unremarkable rain day compared to the more intense, convective-driven totals possible farther east across the central part of the state.
How to Plan Your Sunday Around Limited Dry Time
With rain entering overnight and lingering through most of Sunday, forecasters are urging residents statewide to be prepared to dodge raindrops tomorrow given the limited dry time expected throughout the day. If your plans take you anywhere near the I-80 corridor or points south, keep in mind that convective storms could bring a brief, heavier downpour with little warning, so it’s worth checking radar before heading out rather than assuming a break in the rain will last.
