Mendon, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mendon, a village in Adams County, Illinois.
Tonight
73°F
Partly Cloudy
Partly cloudy, with a low around 73. Southeast wind 6 to 9 mph.
7-day forecast for Mendon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 73°F | Partly Cloudy | 6 to 9 mph SE | 12% |
| Saturday | 91°F | Partly Sunny | 8 mph SW | 8% |
| Saturday Night | 70°F | Chance Showers And Thunderstorms | 6 mph W | 41% |
| Sunday | 80°F | Showers And Thunderstorms Likely | 5 to 9 mph NW | 66% |
| Sunday Night | 62°F | Showers And Thunderstorms Likely | 12 mph NE | 71% |
| Monday | 68°F | Showers And Thunderstorms Likely | 12 mph NE | 71% |
| Monday Night | 56°F | Chance Showers And Thunderstorms | 10 mph NE | 47% |
| Tuesday | 65°F | Slight Chance Rain Showers then Mostly Cloudy | 12 mph NE | 24% |
| Tuesday Night | 52°F | Mostly Cloudy | 6 to 9 mph NE | 6% |
| Wednesday | 68°F | Mostly Sunny | 7 mph NE | 0% |
| Wednesday Night | 55°F | Partly Cloudy | 6 mph NE | 0% |
| Thursday | 70°F | Mostly Sunny | 6 mph NE | 4% |
| Thursday Night | 57°F | Partly Cloudy | 5 mph NE | 5% |
| Friday | 72°F | Mostly Sunny | 6 mph NE | 6% |
Forecast source: National Weather Service (api.weather.gov) for Mendon (40.089, -91.286). Updated through the day.
Growing snapshot for Mendon
Last spring frost
Apr 14
First fall frost
Oct 23
Growing season
191 days
Hardiness zone
6a
More local growing data for Mendon: nearby ZIP 62351 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Adams
Bloomfield
Burton
Camp Point
Clayton
Coatsburg
Columbus
Fall Creek
Fowler
Golden
Kingston
La Prairie
Liberty
Lima
Loraine
Marcelline
Paloma
Payson
Plainville
Quincy
Richfield
Ursa
Climate data from the nearest NOAA station, Quincy Rgnl Ap, Il (12.9 mi from Mendon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.