North Irwin, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for North Irwin, a borough in Westmoreland County, Pennsylvania.
Tonight
66°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms between 8pm and 2am, then showers and thunderstorms. Mostly cloudy, with a low around 66. Southeast wind 2 to 8 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for North Irwin
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 66°F | Chance Showers And Thunderstorms | 2 to 8 mph SE | 84% |
| Sunday | 78°F | Showers And Thunderstorms | 8 to 12 mph SW | 96% |
| Sunday Night | 56°F | Chance Showers And Thunderstorms | 10 mph N | 53% |
| Monday | 70°F | Chance Rain Showers | 13 mph NE | 40% |
| Monday Night | 55°F | Showers And Thunderstorms Likely | 13 mph E | 64% |
| Tuesday | 66°F | Rain Showers Likely | 12 to 17 mph E | 68% |
| Tuesday Night | 52°F | Rain Showers Likely | 18 mph E | 71% |
| Wednesday | 62°F | Rain Showers Likely | 18 mph E | 70% |
| Wednesday Night | 51°F | Chance Rain Showers | 12 to 17 mph E | 46% |
| Thursday | 65°F | Chance Rain Showers | 14 mph E | 46% |
| Thursday Night | 49°F | Slight Chance Rain Showers | 5 to 12 mph E | 16% |
| Friday | 69°F | Slight Chance Rain Showers | 6 to 10 mph NE | 16% |
| Friday Night | 48°F | Partly Cloudy | 5 to 10 mph NE | 13% |
| Saturday | 70°F | Mostly Sunny | 6 to 12 mph N | 11% |
Forecast source: National Weather Service (api.weather.gov) for North Irwin (40.339, -79.711). Updated through the day.
Growing snapshot for North Irwin
Last spring frost
Apr 22
First fall frost
Oct 25
Growing season
186 days
Hardiness zone
6b
More local growing data for North Irwin: nearby ZIP 15647 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
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Irwin
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Climate data from the nearest NOAA station, Murrysville 2 Sw, Pa (4.8 mi from North Irwin). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.