Alleghany, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Alleghany, a community in Sierra County, California.
This Afternoon
71°F
Sunny
Sunny. High near 71, with temperatures falling to around 69 in the afternoon. West wind around 5 mph.
7-day forecast for Alleghany
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 71°F | Sunny | 5 mph W | 0% |
| Tonight | 59°F | Clear | 2 to 7 mph NNE | 0% |
| Saturday | 79°F | Sunny | 2 to 8 mph ESE | 0% |
| Saturday Night | 61°F | Partly Cloudy | 5 mph NNW | 0% |
| Sunday | 77°F | Partly Sunny | 2 to 6 mph SW | 0% |
| Sunday Night | 63°F | Mostly Cloudy | 3 mph ENE | 0% |
| Monday | 78°F | Mostly Sunny | 5 mph W | 2% |
| Monday Night | 61°F | Mostly Clear | 0 to 3 mph S | 0% |
| Tuesday | 79°F | Sunny | 2 to 6 mph W | 0% |
| Tuesday Night | 62°F | Mostly Clear | 3 mph ENE | 0% |
| Wednesday | 81°F | Sunny | 2 to 6 mph SW | 0% |
| Wednesday Night | 64°F | Mostly Clear | 5 mph E | 0% |
| Thursday | 81°F | Sunny | 2 to 6 mph SSE | 0% |
| Thursday Night | 65°F | Partly Cloudy | 5 mph SE | 1% |
Forecast source: National Weather Service (api.weather.gov) for Alleghany (39.467, -120.841). Updated through the day.
Growing snapshot for Alleghany
Last spring frost
Apr 28
First fall frost
Oct 25
Growing season
178 days
Hardiness zone
8b
More local growing data for Alleghany: nearby ZIP 95910 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Downieville, Ca (6.9 mi from Alleghany). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.