Grass Valley, CA Weather & Growing Conditions
Today
55°F
Light Rain
Rain before 3pm, then haze and a chance of rain between 3pm and 5pm, then haze and a chance of rain and patchy fog. Mostly cloudy. High near 55, with temperatures falling to around 49 in the afternoon. South southeast wind 1 to 6 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 55°F | Light Rain | 1 to 6 mph SSE | 91% |
| Tonight | 39°F | Haze | 2 mph ENE | 19% |
| Wednesday | 62°F | Sunny | 3 mph NNW | 0% |
| Wednesday Night | 41°F | Partly Cloudy | 2 mph NE | 0% |
| Thursday | 66°F | Sunny | 0 to 3 mph NNE | 0% |
| Thursday Night | 43°F | Mostly Clear | 3 mph NNW | 0% |
| Friday | 70°F | Sunny | 0 to 3 mph N | 0% |
| Friday Night | 46°F | Mostly Clear | 0 to 5 mph NE | 0% |
| Saturday | 71°F | Sunny | 0 to 3 mph SSE | 0% |
| Saturday Night | 49°F | Mostly Clear | 0 to 5 mph NE | 0% |
| Sunday | 72°F | Mostly Sunny | 0 to 3 mph E | 0% |
| Sunday Night | 49°F | Partly Cloudy | 2 mph NE | 0% |
| Monday | 69°F | Partly Sunny | 2 mph ESE | 4% |
| Monday Night | 48°F | Partly Cloudy | 1 mph NNE | 4% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Grass Valley, CA
Last spring frost
Apr 14
First fall frost
Nov 20
Growing season
218 days
Hardiness zone
9a
Explore more for Grass Valley, CA: full frost dates · planting calendar · California frost dates
Climate data from the nearest NOAA station, Nevada City, Ca (3.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.