Oswego, IL Weather & Growing Conditions
Tonight
59°F
Rain Showers
Rain showers. Cloudy. Low around 59, with temperatures rising to around 61 overnight. South wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 59°F | Rain Showers | 15 mph S | 87% |
| Wednesday | 62°F | Chance Rain Showers | 15 mph SSW | 51% |
| Wednesday Night | 47°F | Slight Chance Rain Showers then Mostly Cloudy | 15 mph SW | 16% |
| Thursday | 57°F | Chance Rain Showers | 10 to 15 mph WSW | 30% |
| Thursday Night | 42°F | Chance Rain Showers | 5 to 10 mph WNW | 36% |
| Friday | 53°F | Slight Chance Rain Showers | 10 to 15 mph N | 23% |
| Friday Night | 35°F | Partly Cloudy | 5 to 10 mph NNW | 4% |
| Saturday | 52°F | Mostly Sunny | 5 mph WNW | 5% |
| Saturday Night | 34°F | Partly Cloudy | 0 to 5 mph WSW | 3% |
| Sunday | 57°F | Mostly Sunny | 5 to 10 mph W | 13% |
| Sunday Night | 35°F | Mostly Clear | 5 to 10 mph WNW | 7% |
| Monday | 61°F | Sunny | 5 to 10 mph WSW | 3% |
| Monday Night | 39°F | Mostly Clear | 5 to 10 mph W | 1% |
| Tuesday | 62°F | Sunny | 5 to 10 mph WNW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Oswego, IL
Last spring frost
Apr 19
First fall frost
Oct 23
Growing season
185 days
Hardiness zone
5b
Explore more for Oswego, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Aurora, Il (7.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.