Raritan, IL Weather & Growing Conditions
Overnight
69°F
Patchy Fog
Patchy fog after 4am. Partly cloudy, with a low around 69. South wind 5 to 10 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 69°F | Patchy Fog | 5 to 10 mph S | 14% |
| Saturday | 85°F | Patchy Fog then Mostly Cloudy | 5 to 10 mph S | 18% |
| Saturday Night | 66°F | Chance Showers And Thunderstorms | 5 mph W | 77% |
| Sunday | 74°F | Showers And Thunderstorms | 5 to 15 mph N | 84% |
| Sunday Night | 59°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 66% |
| Monday | 64°F | Showers And Thunderstorms Likely | 15 mph NE | 66% |
| Monday Night | 53°F | Chance Rain Showers | 10 to 15 mph NE | 50% |
| Tuesday | 62°F | Chance Rain Showers | 10 to 15 mph NE | 29% |
| Tuesday Night | 48°F | Partly Cloudy | 5 to 10 mph NE | 5% |
| Wednesday | 66°F | Mostly Sunny | 5 to 10 mph NE | 0% |
| Wednesday Night | 52°F | Partly Cloudy | 5 mph NE | 1% |
| Thursday | 69°F | Partly Sunny | 5 mph NE | 5% |
| Thursday Night | 54°F | Partly Cloudy | 5 mph NE | 5% |
| Friday | 72°F | Mostly Sunny | 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
Explore more for Raritan, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, La Harpe, Il (10.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.