Mendota, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mendota, a city in Lasalle County, Illinois.
Tonight
65°F
Showers And Thunderstorms
Showers and thunderstorms before 11pm, then a chance of showers and thunderstorms between 11pm and midnight, then showers and thunderstorms likely between midnight and 1am, then patchy fog and showers and thunderstorms. Some of the storms could produce heavy rain. Cloudy. Low around 65, with temperatures rising to around 68 overnight. East wind around 5 mph, with gusts as high as 10 mph. Chance of precipitation is 90%. New rainfall amounts between 1 and 2 inches possible.
7-day forecast for Mendota
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 65°F | Showers And Thunderstorms | 5 mph E | 91% |
| Sunday | 68°F | Patchy Fog | 5 to 15 mph NE | 78% |
| Sunday Night | 56°F | Chance Rain Showers | 15 mph NE | 34% |
| Monday | 64°F | Chance Rain Showers | 15 mph ENE | 53% |
| Monday Night | 53°F | Rain Showers Likely | 10 to 15 mph ENE | 56% |
| Tuesday | 62°F | Rain Showers Likely | 15 mph NE | 56% |
| Tuesday Night | 51°F | Slight Chance Rain Showers then Mostly Cloudy | 10 to 15 mph NE | 16% |
| Wednesday | 65°F | Partly Sunny | 10 mph NE | 6% |
| Wednesday Night | 52°F | Partly Cloudy | 5 to 10 mph NNE | 2% |
| Thursday | 68°F | Mostly Sunny | 5 mph NE | 7% |
| Thursday Night | 54°F | Mostly Cloudy | 0 to 5 mph NE | 7% |
| Friday | 72°F | Partly Sunny | 5 mph NE | 9% |
| Friday Night | 54°F | Partly Cloudy | 0 to 5 mph NE | 9% |
| Saturday | 73°F | Mostly Sunny | 0 to 5 mph ENE | 4% |
Forecast source: National Weather Service (api.weather.gov) for Mendota (41.557, -89.101). Updated through the day.
Growing snapshot for Mendota
Last spring frost
Apr 27
First fall frost
Oct 15
Growing season
171 days
Hardiness zone
5b
More local growing data for Mendota: nearby ZIP 61342 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Cedar Point
Dana
Dayton
Earlville
Grand Ridge
Harding
Kangley
LaSalle
Leland
Leonore
Lostant
Marseilles
Millington
Naplate
Newark
North Utica
Oglesby
Ottawa
Peru
Ransom
Rutland
Seneca
Serena
Sheridan
Streator
Tonica
Triumph
Troy Grove
Wedron
Wenona
Climate data from the nearest NOAA station, Paw Paw 2S, Il (10 mi from Mendota). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.