Grass Valley, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Grass Valley, a city in Nevada County, California.
This Afternoon
83°F
Sunny
Sunny, with a high near 83. West wind around 2 mph.
7-day forecast for Grass Valley
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 83°F | Sunny | 2 mph W | 0% |
| Tonight | 58°F | Mostly Clear | 1 to 5 mph ESE | 0% |
| Sunday | 82°F | Partly Sunny | 1 to 5 mph S | 0% |
| Sunday Night | 59°F | Mostly Cloudy | 1 mph NE | 0% |
| Monday | 81°F | Mostly Sunny | 1 to 5 mph SW | 0% |
| Monday Night | 57°F | Mostly Clear | 0 to 3 mph E | 0% |
| Tuesday | 81°F | Sunny | 0 to 3 mph N | 0% |
| Tuesday Night | 57°F | Clear | 2 mph ESE | 0% |
| Wednesday | 85°F | Sunny | 3 mph NNW | 0% |
| Wednesday Night | 59°F | Mostly Clear | 3 mph NNW | 0% |
| Thursday | 88°F | Sunny | 2 to 6 mph SSE | 0% |
| Thursday Night | 61°F | Mostly Clear | 5 mph ESE | 0% |
| Friday | 84°F | Sunny | 5 mph SSE | 0% |
| Friday Night | 59°F | Mostly Clear | 5 mph SE | 1% |
Forecast source: National Weather Service (api.weather.gov) for Grass Valley (39.220, -121.053). Updated through the day.
Growing snapshot for Grass Valley
Last spring frost
Apr 14
First fall frost
Nov 20
Growing season
218 days
Hardiness zone
9a
More local growing data for Grass Valley: nearby ZIP 95945 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
Alta Sierra
Floriston
Graniteville
Lake Wildwood
Nevada City
Penn Valley
Rough and Ready
Truckee
Washington
Climate data from the nearest NOAA station, Nevada City, Ca (3.9 mi from Grass Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.