San Jose, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for San Jose, a village in Mason County, Illinois.
This Afternoon
83°F
Mostly Sunny
Mostly sunny, with a high near 83. East wind around 8 mph.
7-day forecast for San Jose
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 83°F | Mostly Sunny | 8 mph E | 12% |
| Tonight | 70°F | Partly Cloudy | 9 mph ESE | 5% |
| Saturday | 90°F | Slight Chance Rain Showers then Mostly Cloudy | 8 mph SSW | 17% |
| Saturday Night | 68°F | Slight Chance Showers And Thunderstorms | 7 mph SE | 41% |
| Sunday | 81°F | Showers And Thunderstorms Likely | 3 to 12 mph NNE | 62% |
| Sunday Night | 60°F | Showers And Thunderstorms Likely | 9 to 14 mph NE | 64% |
| Monday | 68°F | Showers And Thunderstorms Likely | 13 mph ENE | 64% |
| Monday Night | 54°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 47% |
| Tuesday | 66°F | Slight Chance Rain Showers then Mostly Cloudy | 12 mph NE | 24% |
| Tuesday Night | 51°F | Mostly Cloudy | 6 to 10 mph NNE | 5% |
| Wednesday | 69°F | Partly Sunny | 8 mph NNE | 3% |
| Wednesday Night | 53°F | Partly Cloudy | 3 to 7 mph NNE | 1% |
| Thursday | 71°F | Mostly Sunny | 3 to 7 mph NNE | 3% |
| Thursday Night | 55°F | Partly Cloudy | 2 to 6 mph NNE | 3% |
Forecast source: National Weather Service (api.weather.gov) for San Jose (40.305, -89.605). Updated through the day.
Growing snapshot for San Jose
Last spring frost
Apr 17
First fall frost
Oct 18
Growing season
182 days
Hardiness zone
6a
More local growing data for San Jose: nearby ZIP 62682 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Mason City 4Se, Il (9.4 mi from San Jose). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.