Mammoth, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mammoth, a community in Westmoreland County, Pennsylvania.
Tonight
58°F
Partly Cloudy
Partly cloudy, with a low around 58. Northeast wind 2 to 6 mph.
7-day forecast for Mammoth
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 58°F | Partly Cloudy | 2 to 6 mph NE | 13% |
| Saturday | 79°F | Partly Sunny | 6 mph SE | 2% |
| Saturday Night | 65°F | Partly Cloudy then Chance Showers And Thunderstorms | 6 to 12 mph SE | 50% |
| Sunday | 78°F | Showers And Thunderstorms | 6 to 12 mph SW | 95% |
| Sunday Night | 61°F | Showers And Thunderstorms | 7 mph N | 95% |
| Monday | 71°F | Chance Rain Showers | 7 to 10 mph NE | 45% |
| Monday Night | 58°F | Showers And Thunderstorms Likely | 12 to 15 mph E | 69% |
| Tuesday | 66°F | Showers And Thunderstorms Likely | 15 to 20 mph E | 73% |
| Tuesday Night | 55°F | Showers And Thunderstorms Likely | 21 mph E | 70% |
| Wednesday | 63°F | Showers And Thunderstorms Likely | 20 mph E | 65% |
| Wednesday Night | 54°F | Chance Showers And Thunderstorms | 12 to 20 mph E | 53% |
| Thursday | 65°F | Chance Rain Showers | 10 mph E | 46% |
| Thursday Night | 53°F | Chance Rain Showers | 3 to 9 mph E | 28% |
| Friday | 70°F | Slight Chance Rain Showers | 3 to 8 mph NE | 24% |
Forecast source: National Weather Service (api.weather.gov) for Mammoth (40.199, -79.463). Updated through the day.
Growing snapshot for Mammoth
Last spring frost
May 1
First fall frost
Oct 13
Growing season
164 days
Hardiness zone
6b
More local growing data for Mammoth: nearby ZIP 15674 weather · frost dates · planting calendar · Pennsylvania frost dates
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Climate data from the nearest NOAA station, Mt Pleasant, Pa (0.6 mi from Mammoth). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.