Mercer, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mercer, a borough in Mercer County, Pennsylvania.
Tonight
63°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Cloudy, with a low around 63. Southeast wind around 5 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for Mercer
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 63°F | Showers And Thunderstorms Likely | 5 mph SE | 66% |
| Sunday | 74°F | Showers And Thunderstorms | 6 to 9 mph W | 93% |
| Sunday Night | 51°F | Slight Chance Showers And Thunderstorms then Mostly Cloudy | 7 to 10 mph NE | 19% |
| Monday | 69°F | Mostly Cloudy | 10 mph NE | 10% |
| Monday Night | 50°F | Chance Rain Showers | 12 mph NE | 30% |
| Tuesday | 64°F | Chance Rain Showers | 15 mph E | 41% |
| Tuesday Night | 50°F | Rain Showers Likely | 17 mph E | 67% |
| Wednesday | 63°F | Rain Showers Likely | 17 mph E | 67% |
| Wednesday Night | 49°F | Chance Rain Showers | 13 to 16 mph E | 50% |
| Thursday | 65°F | Chance Rain Showers | 9 to 14 mph E | 50% |
| Thursday Night | 48°F | Slight Chance Rain Showers then Mostly Cloudy | 5 to 8 mph E | 16% |
| Friday | 69°F | Partly Sunny | 8 mph NE | 12% |
| Friday Night | 48°F | Partly Cloudy | 5 to 8 mph NE | 11% |
| Saturday | 71°F | Mostly Sunny | 6 to 9 mph NE | 7% |
Forecast source: National Weather Service (api.weather.gov) for Mercer (41.227, -80.236). Updated through the day.
Growing snapshot for Mercer
Last spring frost
May 15
First fall frost
Oct 3
Growing season
140 days
Hardiness zone
6a
More local growing data for Mercer: nearby ZIP 16137 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Clark
Farrell
Fredonia
Greenville
Grove City
Hermitage
Jackson Center
Lake Latonka
New Lebanon
Reynolds Heights
Sandy Lake
Sharon
Sharpsville
Sheakleyville
Stoneboro
West Middlesex
Wheatland
Climate data from the nearest NOAA station, Mercer, Pa (0.5 mi from Mercer). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.