Osco, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Osco, a community in Henry County, Illinois.
Today
56°F
Slight Chance Rain Showers
A slight chance of rain showers between 10am and 4pm. Mostly cloudy, with a high near 56. Southwest wind 15 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.
7-day forecast for Osco
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 56°F | Slight Chance Rain Showers | 15 to 20 mph SW | 23% |
| Tonight | 46°F | Mostly Cloudy | 15 mph SW | 10% |
| Thursday | 56°F | Chance Rain Showers | 10 to 15 mph W | 35% |
| Thursday Night | 42°F | Slight Chance Rain Showers then Mostly Cloudy | 10 mph NW | 22% |
| Friday | 50°F | Partly Sunny | 10 to 15 mph N | 7% |
| Friday Night | 32°F | Partly Cloudy | 0 to 5 mph N | 0% |
| Saturday | 52°F | Sunny | 0 to 5 mph NW | 0% |
| Saturday Night | 34°F | Mostly Clear | 5 mph W | 2% |
| Sunday | 57°F | Sunny | 5 to 10 mph W | 1% |
| Sunday Night | 36°F | Clear | 5 mph W | 1% |
| Monday | 63°F | Sunny | 5 to 10 mph SW | 0% |
| Monday Night | 40°F | Mostly Clear | 5 to 10 mph W | 0% |
| Tuesday | 64°F | Sunny | 5 mph NW | 0% |
| Tuesday Night | 40°F | Partly Cloudy | 0 to 5 mph N | 0% |
Forecast source: National Weather Service (api.weather.gov) for Osco (41.347, -90.283). Updated through the day.
Growing snapshot for Osco
Last spring frost
Apr 20
First fall frost
Oct 20
Growing season
180 days
Hardiness zone
5b
More local growing data for Osco: nearby ZIP 61274 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Alpha
Andover
Annawan
Atkinson
Bishop Hill
Cambridge
Cleveland
Colona
Galva
Geneseo
Hooppole
Kewanee
Lynn Center
Ophiem
Orion
Swedona
Woodhull
Climate data from the nearest NOAA station, Geneseo, Il (8.7 mi from Osco). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.