Allegheny, PA Weather Forecast
Westmoreland County, Pennsylvania
Seven-day outlook
36–72°F across the weekThe week runs between 38° and 72°, with today the warmest day of it. There is no real trend across it: one day looks much like the next. Wednesday is the wettest day, peaking near 27%. 6 of the 7 days stay dry.
Forecasts come from the National Weather Service's own computer models, and current conditions from the nearest reporting weather station. Both are served through the weather API. A forecast is guidance, not a warning, and anything the Weather Service has actually issued is on the live map.
The written summaries on this page are generated from the forecast data above, not by a meteorologist. Each sentence is a reading of the same numbers you can see, and no forecaster has reviewed them.
About the Allegheny forecast
Allegheny sits at 40.6149°N, 79.6397°W in Westmoreland County, Pennsylvania. The forecast above is drawn for that point from the National Weather Service's own computer models: a seven-day outlook, and a finer-grained one covering the next eighteen hours where it reaches, and the radar and alert panels show what the Weather Service has out over the area right now.
- County
- Westmoreland County
- Coordinates
- 40.6149°N, 79.6397°W
- Population
- 8,201 · 2023 estimate
- Land area
- 31.059 sq mi
Place data from the US Census Bureau. Coordinates are the Census internal point for Allegheny, and the forecast is for that location, not for every address inside the city limits, and a large city can have real weather differences from one side to the other.
How well can the network see Allegheny?
The nearest Doppler radar is KPBZ (Pittsburgh, PA), 31 miles to the W. A WSR-88D's lowest routine scan sits half a degree above horizontal, and the earth curves away beneath it, so by the time that beam reaches Allegheny its center is about 1,900 ft above ground. That is about as close as radar coverage gets in the United States: the lowest scan is still near the ground when it reaches Allegheny, so low-level rotation and the leading edge of a gust front show up on it. Allegheny is closer to its radar than 69% of US cities.
The closest instrument actually measuring the air is KBTP · Pittsburgh/Butler Rgnl on the ASOS/AWOS network, 20 miles away. Far enough that "current conditions" for Allegheny is an educated reading of somewhere else, worth knowing before you plan around a single temperature.
Beam height is the standard 4/3-earth approximation for the 0.5° scan and assumes normal refraction; it is where the center of the beam is, not its edges, and unusual temperature profiles bend it. Radar siting from the NWS WSR-88D network, station positions from the Pennsylvania observing network as of this build.
Forecasts near Allegheny
- Vandergrift, PA4 mi
- Harrison, PA4 mi
- Lower Burrell, PA5 mi
- Brackenridge, PA5 mi
- Tarentum, PA6 mi
- New Kensington, PA7 mi
- Arnold, PA7 mi
- Washington, PA7 mi
Elsewhere in Pennsylvania
PhiladelphiaPittsburghAllentownReadingErieUpper DarbyAll Pennsylvania forecasts →