Raritan, IL Weather & Growing Conditions
Tonight
70°F
Mostly Cloudy then Chance Showers And Thunderstorms
A chance of showers and thunderstorms after 4am. Mostly cloudy, with a low around 70. Southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 70°F | Mostly Cloudy then Chance Showers And Thunderstorms | 10 mph SE | 25% |
| Saturday | 86°F | Slight Chance Rain Showers then Mostly Cloudy | 5 to 10 mph S | 19% |
| Saturday Night | 66°F | Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 5 mph NW | 73% |
| Sunday | 75°F | Showers And Thunderstorms Likely | 5 to 10 mph NE | 73% |
| Sunday Night | 58°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 10 to 15 mph NE | 70% |
| Monday | 65°F | Showers And Thunderstorms Likely | 10 to 15 mph NE | 66% |
| Monday Night | 54°F | Chance Rain Showers | 10 to 15 mph NE | 50% |
| Tuesday | 63°F | Chance Rain Showers | 10 mph NE | 30% |
| Tuesday Night | 49°F | Mostly Cloudy | 5 to 10 mph NE | 6% |
| Wednesday | 67°F | Mostly Sunny | 5 mph NE | 2% |
| Wednesday Night | 52°F | Partly Cloudy | 0 to 5 mph NE | 1% |
| Thursday | 69°F | Partly Sunny | 5 mph NE | 4% |
| Thursday Night | 54°F | Partly Cloudy | 0 to 5 mph NE | 5% |
| Friday | 71°F | Mostly Sunny | 0 to 5 mph NE | 5% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Raritan, IL
Last spring frost
Apr 21
First fall frost
Oct 19
Growing season
180 days
Hardiness zone
5b
Explore more for Raritan, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, La Harpe, Il (12 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.