LaSalle, IL Weather & Growing Conditions
Today
85°F
Mostly Sunny
Mostly sunny, with a high near 85. South southwest wind 5 to 10 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 85°F | Mostly Sunny | 5 to 10 mph SSW | 0% |
| Tonight | 68°F | Mostly Cloudy then Slight Chance Showers And Thunderstorms | 5 mph S | 22% |
| Wednesday | 80°F | Chance Showers And Thunderstorms | 5 mph W | 58% |
| Wednesday Night | 65°F | Showers And Thunderstorms | 5 mph N | 87% |
| Thursday | 79°F | Chance Showers And Thunderstorms | 0 to 5 mph E | 62% |
| Thursday Night | 63°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph SE | 22% |
| Friday | 82°F | Mostly Sunny | 0 to 5 mph SSE | 7% |
| Friday Night | 65°F | Mostly Clear | 0 to 5 mph S | 9% |
| Saturday | 85°F | Mostly Sunny | 5 mph SSW | 9% |
| Saturday Night | 70°F | Mostly Clear then Slight Chance Showers And Thunderstorms | 5 to 10 mph SSW | 15% |
| Sunday | 87°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 10 to 15 mph SW | 15% |
| Sunday Night | 71°F | Slight Chance Showers And Thunderstorms | 5 to 10 mph SSW | 31% |
| Monday | 86°F | Chance Showers And Thunderstorms | 5 to 10 mph SSW | 31% |
| Monday Night | 71°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 10 mph WSW | 38% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for LaSalle, IL
Last spring frost
Apr 24
First fall frost
Oct 18
Growing season
176 days
Hardiness zone
5b
Explore more for LaSalle, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Peru, Il (3.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.