Rio, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Rio, a village in Knox County, Illinois.
This Afternoon
68°F
Light Rain
Rain and a slight chance of thunderstorms. Mostly cloudy, with a high near 68. South southeast wind around 18 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 for Rio
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 68°F | Light Rain | 18 mph SSE | 90% |
| Tonight | 51°F | Light Rain | 13 to 18 mph S | 79% |
| Wednesday | 57°F | Chance Light Rain | 17 mph SW | 26% |
| Wednesday Night | 45°F | Mostly Cloudy | 12 to 15 mph WSW | 10% |
| Thursday | 56°F | Chance Light Rain | 9 to 15 mph W | 27% |
| Thursday Night | 42°F | Chance Light Rain then Mostly Cloudy | 6 to 9 mph NW | 31% |
| Friday | 52°F | Partly Sunny | 7 to 12 mph N | 13% |
| Friday Night | 34°F | Partly Cloudy | 1 to 6 mph NNW | 1% |
| Saturday | 52°F | Partly Sunny | 1 to 6 mph WNW | 3% |
| Saturday Night | 35°F | Partly Cloudy | 1 to 5 mph W | 3% |
| Sunday | 59°F | Sunny | 5 to 10 mph W | 11% |
| Sunday Night | 36°F | Mostly Clear | 6 mph W | 3% |
| Monday | 63°F | Sunny | 5 to 13 mph SW | 1% |
| Monday Night | 40°F | Mostly Clear | 5 to 8 mph W | 0% |
Forecast source: National Weather Service (api.weather.gov) for Rio (41.109, -90.399). Updated through the day.
Growing snapshot for Rio
Last spring frost
Apr 20
First fall frost
Oct 19
Growing season
180 days
Hardiness zone
5b
More local growing data for Rio: nearby ZIP 61472 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Abingdon
Altona
East Galesburg
Galesburg
Gilson
Henderson
Knoxville
Maquon
Nekoma
Oak Run
Oneida
St. Augustine
Victoria
Wataga
Williamsfield
Yates City
Climate data from the nearest NOAA station, Galesburg, Il (10.8 mi from Rio). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.