Unionville, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Unionville, a community in Chester County, Pennsylvania.
This Afternoon
81°F
Mostly Sunny
Mostly sunny, with a high near 81. North wind around 10 mph.
7-day forecast for Unionville
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 81°F | Mostly Sunny | 10 mph N | 0% |
| Tonight | 57°F | Partly Cloudy | 5 mph N | 0% |
| Saturday | 73°F | Mostly Sunny | 5 mph NE | 2% |
| Saturday Night | 62°F | Patchy Fog | 5 mph SE | 22% |
| Sunday | 76°F | Showers And Thunderstorms | 5 to 10 mph S | 81% |
| Sunday Night | 61°F | Showers And Thunderstorms | 5 to 10 mph NW | 83% |
| Monday | 69°F | Chance Rain Showers | 10 mph NE | 40% |
| Monday Night | 55°F | Chance Rain Showers | 5 to 10 mph NE | 33% |
| Tuesday | 62°F | Chance Rain Showers | 10 mph NE | 40% |
| Tuesday Night | 52°F | Chance Rain Showers | 10 to 15 mph NE | 40% |
| Wednesday | 60°F | Chance Rain Showers | 10 to 15 mph NE | 39% |
| Wednesday Night | 51°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 39% |
| Thursday | 61°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 37% |
| Thursday Night | 51°F | Chance Showers And Thunderstorms | 5 to 10 mph NE | 33% |
Forecast source: National Weather Service (api.weather.gov) for Unionville (39.901, -75.730). Updated through the day.
Growing snapshot for Unionville
Last spring frost
Apr 19
First fall frost
Oct 26
Growing season
189 days
Hardiness zone
7a
More local growing data for Unionville: nearby ZIP 19375 weather · frost dates · planting calendar · Pennsylvania frost dates
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Climate data from the nearest NOAA station, Avondale 2 N, Pa (3.8 mi from Unionville). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.