Tredyffrin, PA Weather Forecast
Chester County, Pennsylvania
Seven-day outlook
41–70°F across the weekThe week runs between 41° and 70°, with tomorrow the warmest day of it. There is no real trend across it: one day looks much like the next. Every day in the outlook stays 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 Tredyffrin forecast
Tredyffrin sits at 40.0675°N, 75.4503°W in Chester 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
- Chester County
- Coordinates
- 40.0675°N, 75.4503°W
- Population
- 31,787 · 2023 estimate
- Land area
- 19.766 sq mi
Place data from the US Census Bureau. Coordinates are the Census internal point for Tredyffrin, 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 Tredyffrin?
The nearest Doppler radar is KDIX (Philadelphia, PA), 56 miles to the E. 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 Tredyffrin its center is about 4,100 ft above ground. That is far enough out that the beam has climbed above the lowest few thousand feet. Storm structure aloft is visible; a shallow circulation near the ground may not be, and a warning here can arrive before anything looks dramatic on the radar picture.
The closest instrument actually measuring the air is KOQN · West Chester/Brandywine Rgnl on the ASOS/AWOS network, 8.8 miles away. Near enough to be representative on most days, though a summer thunderstorm can soak one and miss the other entirely.
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 Tredyffrin
- Easttown, PA3 mi
- Schuylkill, PA4 mi
- Upper Merion, PA4 mi
- Malvern, PA4 mi
- Radnor, PA5 mi
- Willistown, PA5 mi
- Newtown, PA6 mi
- East Whiteland, PA6 mi
Elsewhere in Pennsylvania
PhiladelphiaPittsburghAllentownReadingErieUpper DarbyAll Pennsylvania forecasts →