Pennington, NJ Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Pennington, a borough in Mercer County, New Jersey.
Tonight
59°F
Mostly Cloudy
Mostly cloudy, with a low around 59. East wind 0 to 5 mph.
7-day forecast for Pennington
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 59°F | Mostly Cloudy | 0 to 5 mph E | 7% |
| Sunday | 75°F | Showers And Thunderstorms | 5 to 10 mph SE | 78% |
| Sunday Night | 57°F | Showers And Thunderstorms Likely | 5 to 10 mph W | 63% |
| Monday | 70°F | Partly Sunny then Chance Rain Showers | 5 to 10 mph NE | 29% |
| Monday Night | 52°F | Chance Rain Showers | 5 to 10 mph NE | 30% |
| Tuesday | 65°F | Chance Rain Showers | 10 mph NE | 36% |
| Tuesday Night | 51°F | Chance Rain Showers then Mostly Cloudy | 10 mph NE | 36% |
| Wednesday | 64°F | Slight Chance Rain Showers | 10 to 15 mph NE | 21% |
| Wednesday Night | 51°F | Slight Chance Rain Showers | 10 to 15 mph NE | 22% |
| Thursday | 63°F | Chance Rain Showers | 10 to 15 mph NE | 27% |
| Thursday Night | 50°F | Chance Rain Showers | 10 mph NE | 35% |
| Friday | 66°F | Chance Rain Showers | 10 to 15 mph N | 35% |
| Friday Night | 50°F | Chance Rain Showers | 10 mph N | 34% |
| Saturday | 70°F | Chance Rain Showers | 10 mph N | 30% |
Forecast source: National Weather Service (api.weather.gov) for Pennington (40.325, -74.789). Updated through the day.
Growing snapshot for Pennington
Last spring frost
Apr 10
First fall frost
Nov 1
Growing season
202 days
Hardiness zone
7a
More local growing data for Pennington: nearby ZIP 08534 weather · frost dates · planting calendar · New Jersey frost dates
Nearby towns & communities
Allentown
Groveville
Hamilton Square
Hightstown
Hopewell
Lawrenceville
Mercerville
Princeton
Robbinsville Center
The College of New Jersey
Titusville
Trenton
Twin Rivers
White Horse
Windsor
Yardville
Climate data from the nearest NOAA station, Trenton Mercer Co Ap, Nj (3.8 mi from Pennington). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.