Thornburg, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Thornburg, a borough in Allegheny County, Pennsylvania.
Overnight
54°F
Mostly Clear
Mostly clear, with a low around 54. East wind 0 to 3 mph.
7-day forecast for Thornburg
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 54°F | Mostly Clear | 0 to 3 mph E | 1% |
| Wednesday | 78°F | Mostly Cloudy then Slight Chance Light Rain | 0 to 10 mph S | 24% |
| Wednesday Night | 61°F | Light Rain | 8 to 12 mph S | 95% |
| Thursday | 69°F | Slight Chance Light Rain then Partly Sunny | 7 to 13 mph SW | 17% |
| Thursday Night | 49°F | Partly Cloudy | 1 to 6 mph SW | 1% |
| Friday | 63°F | Partly Sunny then Slight Chance Light Rain | 2 to 8 mph SW | 20% |
| Friday Night | 43°F | Chance Light Rain | 5 to 8 mph W | 32% |
| Saturday | 53°F | Chance Light Rain | 8 to 12 mph W | 30% |
| Saturday Night | 38°F | Slight Chance Light Rain | 5 to 9 mph W | 24% |
| Sunday | 55°F | Partly Sunny | 6 to 13 mph W | 6% |
| Sunday Night | 36°F | Partly Cloudy | 9 mph W | 5% |
| Monday | 57°F | Mostly Sunny | 7 to 13 mph W | 10% |
| Monday Night | 38°F | Mostly Clear | 8 mph SW | 8% |
| Tuesday | 61°F | Sunny | 9 to 14 mph SW | 3% |
Forecast source: National Weather Service (api.weather.gov) for Thornburg (40.435, -80.084). Updated through the day.
Growing snapshot for Thornburg
Last spring frost
Apr 24
First fall frost
Oct 27
Growing season
186 days
Hardiness zone
6b
More local growing data for Thornburg: nearby ZIP 15205 weather · frost dates · planting calendar · Pennsylvania frost dates
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Climate data from the nearest NOAA station, Emsworth L/D Ohio Rvr, Pa (4.7 mi from Thornburg). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.