Mendon, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mendon, a village in Adams County, Illinois.
Today
89°F
Sunny
Sunny, with a high near 89. South wind 5 to 8 mph.
7-day forecast for Mendon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 89°F | Sunny | 5 to 8 mph S | 0% |
| Tonight | 70°F | Partly Cloudy | 3 to 8 mph SE | 14% |
| Wednesday | 85°F | Scattered Showers And Thunderstorms | 6 mph S | 52% |
| Wednesday Night | 67°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 7 mph NE | 89% |
| Thursday | 82°F | Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 mph SE | 89% |
| Thursday Night | 66°F | Partly Cloudy | 3 mph SE | 6% |
| Friday | 85°F | Mostly Sunny | 3 mph S | 7% |
| Friday Night | 68°F | Chance Showers And Thunderstorms | 5 mph S | 31% |
| Saturday | 88°F | Slight Chance Showers And Thunderstorms then Sunny | 7 mph SW | 24% |
| Saturday Night | 72°F | Mostly Clear | 6 to 10 mph S | 6% |
| Sunday | 90°F | Sunny | 9 to 13 mph SW | 4% |
| Sunday Night | 73°F | Mostly Clear | 12 mph S | 13% |
| Monday | 91°F | Mostly Sunny | 12 mph SW | 13% |
| Monday Night | 73°F | Slight Chance Showers And Thunderstorms | 9 mph S | 25% |
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 Aug 4, 2026.