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Portersville, PA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Portersville, a borough in Butler County, Pennsylvania.

Today
74°F
Partly Sunny then Chance Light Rain
A chance of rain after 1pm. Partly sunny, with a high near 74. South wind 5 to 9 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Portersville

WhenTempForecastWindPrecip
Today 74°F Partly Sunny then Chance Light Rain 5 to 9 mph S 41%
Tonight 58°F Light Rain 10 mph S 95%
Thursday 67°F Partly Sunny 6 to 10 mph SW 8%
Thursday Night 45°F Partly Cloudy 5 mph SW 0%
Friday 60°F Partly Sunny then Slight Chance Light Rain 2 to 7 mph SW 20%
Friday Night 39°F Chance Light Rain 3 to 7 mph W 48%
Saturday 51°F Chance Light Rain 7 to 10 mph W 41%
Saturday Night 33°F Chance Light Rain 5 to 8 mph W 35%
Sunday 53°F Partly Sunny 5 to 10 mph W 8%
Sunday Night 32°F Partly Cloudy 7 mph W 7%
Monday 54°F Slight Chance Light Rain 6 to 9 mph W 16%
Monday Night 32°F Slight Chance Light Rain then Mostly Clear 3 to 7 mph SW 16%
Tuesday 58°F Mostly Sunny 7 to 12 mph SW 4%
Tuesday Night 32°F Partly Cloudy 2 to 6 mph W 4%

Forecast source: National Weather Service (api.weather.gov) for Portersville (40.924, -80.147). Updated through the day.

Growing snapshot for Portersville

Last spring frost
May 7
First fall frost
Oct 14
Growing season
158 days
Hardiness zone
6a

More local growing data for Portersville: nearby ZIP 16051 weather · frost dates · planting calendar · Pennsylvania frost dates

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Climate data from the nearest NOAA station, Slippery Rock 1 Ssw, Pa (8.9 mi from Portersville). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.