Rio Oso, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Rio Oso, a community in Sutter County, California.
Today
61°F
Light Rain
Rain before 3pm, then haze and a chance of rain. Mostly cloudy. High near 61, with temperatures falling to around 56 in the afternoon. Southeast wind around 6 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for Rio Oso
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 61°F | Light Rain | 6 mph SE | 92% |
| Tonight | 45°F | Partly Cloudy | 6 mph NNW | 14% |
| Wednesday | 69°F | Sunny | 2 to 8 mph NW | 0% |
| Wednesday Night | 43°F | Areas Of Fog | 2 mph N | 0% |
| Thursday | 72°F | Sunny | 5 mph NNW | 0% |
| Thursday Night | 41°F | Mostly Clear then Patchy Fog | 2 mph NE | 0% |
| Friday | 72°F | Patchy Fog then Sunny | 2 mph NNW | 0% |
| Friday Night | 44°F | Mostly Clear | 2 mph ENE | 0% |
| Saturday | 73°F | Sunny | 2 mph WNW | 0% |
| Saturday Night | 45°F | Mostly Clear | 1 mph SSE | 0% |
| Sunday | 73°F | Mostly Sunny | 3 mph NW | 0% |
| Sunday Night | 46°F | Partly Cloudy | 1 mph E | 0% |
| Monday | 72°F | Partly Sunny | 2 mph S | 1% |
| Monday Night | 46°F | Partly Cloudy | 1 mph NE | 1% |
Forecast source: National Weather Service (api.weather.gov) for Rio Oso (38.952, -121.531). Updated through the day.
Growing snapshot for Rio Oso
Last spring frost
Feb 11
First fall frost
Nov 30
Growing season
289 days
Hardiness zone
9b
More local growing data for Rio Oso: nearby ZIP 95674 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Marysville Yuba Co Ap, Ca (11.2 mi from Rio Oso). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.