South River, NJ Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for South River, a borough in Middlesex County, New Jersey.
Today
84°F
Mostly Sunny
Mostly sunny, with a high near 84. Northeast wind 0 to 5 mph.
7-day forecast for South River
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Mostly Sunny | 0 to 5 mph NE | 0% |
| Tonight | 65°F | Mostly Cloudy | 0 to 5 mph SE | 1% |
| Wednesday | 84°F | Mostly Cloudy then Chance Showers And Thunderstorms | 0 to 5 mph E | 50% |
| Wednesday Night | 71°F | Chance Showers And Thunderstorms | 0 to 5 mph S | 41% |
| Thursday | 90°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 0 to 5 mph SW | 35% |
| Thursday Night | 73°F | Chance Showers And Thunderstorms | 5 mph SW | 35% |
| Friday | 91°F | Mostly Sunny then Chance Showers And Thunderstorms | 5 mph SW | 43% |
| Friday Night | 71°F | Chance Showers And Thunderstorms | 0 to 5 mph SW | 44% |
| Saturday | 89°F | Partly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph W | 37% |
| Saturday Night | 70°F | Chance Showers And Thunderstorms | 0 to 5 mph W | 37% |
| Sunday | 89°F | Mostly Sunny | 0 to 5 mph W | 14% |
| Sunday Night | 72°F | Mostly Clear | 0 to 5 mph SW | 14% |
| Monday | 91°F | Mostly Sunny | 0 to 10 mph W | 8% |
| Monday Night | 71°F | Partly Cloudy | 5 mph W | 12% |
Forecast source: National Weather Service (api.weather.gov) for South River (40.446, -74.378). Updated through the day.
Growing snapshot for South River
Last spring frost
Apr 15
First fall frost
Oct 26
Growing season
193 days
Hardiness zone
7a
More local growing data for South River: nearby ZIP 08882 weather · frost dates · planting calendar · New Jersey frost dates
Nearby towns & communities
Avenel
Brownville
Carteret
Clearbrook
Colonia
Concordia
Cranbury
Dayton
Deans
East Franklin
Encore at Monroe
Fords
Forsgate
Heathcote
Helmetta
Highland Park
Hopelawn
Iselin
Jamesburg
Keasbey
Kendall Park
Madison Park
Matawan
Menlo Park Terrace
Metuchen
Middlesex
Milltown
Monmouth Junction
New Brunswick
Old Bridge
Climate data from the nearest NOAA station, New Brunswick 3 Se, Nj (3 mi from South River). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.