Unionville, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Unionville, a community in Chester County, Pennsylvania.
This Afternoon
83°F
Mostly Sunny
Mostly sunny, with a high near 83. East wind 0 to 5 mph.
7-day forecast for Unionville
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 83°F | Mostly Sunny | 0 to 5 mph E | 0% |
| Tonight | 66°F | Mostly Cloudy | 0 mph | 11% |
| Wednesday | 82°F | Showers And Thunderstorms Likely | 0 to 5 mph E | 79% |
| Wednesday Night | 70°F | Chance Showers And Thunderstorms | 5 mph S | 52% |
| Thursday | 86°F | Mostly Sunny then Chance Showers And Thunderstorms | 5 to 10 mph SW | 26% |
| Thursday Night | 71°F | Chance Showers And Thunderstorms | 5 to 10 mph SW | 37% |
| Friday | 87°F | Mostly Sunny then Chance Showers And Thunderstorms | 5 mph SW | 44% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 0 to 5 mph SW | 44% |
| Saturday | 85°F | Partly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph W | 40% |
| Saturday Night | 69°F | Chance Showers And Thunderstorms | 0 to 5 mph W | 40% |
| Sunday | 86°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 5 mph W | 16% |
| Sunday Night | 70°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph SW | 16% |
| Monday | 88°F | Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph W | 17% |
| Monday Night | 70°F | Slight Chance Showers And Thunderstorms | 5 mph W | 18% |
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
Nearby towns & communities
Atglen
Avondale
Berwyn
Caln
Chadds Ford
Chesterbrook
Christiana
Coatesville
Cochranville
Devon
Downingtown
Eagle
Eagleview
Elverson
Exton
Frazer
Glenmoore
Hamorton
Hayti
Honey Brook
Kennett Square
Kimberton
Lincoln University
Lionville
Little Britain
Malvern
Marshallton
Modena
Nottingham
Oxford
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 Aug 4, 2026.