Rock Falls, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Rock Falls, a city in Whiteside County, Illinois.
This Afternoon
68°F
Showers And Thunderstorms
Showers and thunderstorms. Mostly cloudy. High near 68, with temperatures falling to around 66 in the afternoon. South wind 15 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 100%.
7-day forecast for Rock Falls
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 68°F | Showers And Thunderstorms | 15 to 20 mph S | 95% |
| Tonight | 53°F | Showers And Thunderstorms | 15 mph S | 80% |
| Wednesday | 57°F | Chance Rain Showers | 15 mph SW | 35% |
| Wednesday Night | 45°F | Slight Chance Rain Showers | 10 to 15 mph SW | 24% |
| Thursday | 54°F | Chance Rain Showers | 10 mph W | 50% |
| Thursday Night | 41°F | Chance Rain Showers | 5 to 10 mph NW | 27% |
| Friday | 52°F | Slight Chance Rain Showers then Partly Sunny | 5 to 10 mph N | 15% |
| Friday Night | 33°F | Partly Cloudy | 0 to 5 mph N | 1% |
| Saturday | 52°F | Mostly Sunny | 0 to 5 mph W | 3% |
| Saturday Night | 34°F | Partly Cloudy | 0 mph | 4% |
| Sunday | 58°F | Mostly Sunny | 0 to 10 mph W | 12% |
| Sunday Night | 34°F | Mostly Clear | 0 to 5 mph W | 4% |
| Monday | 62°F | Sunny | 0 to 10 mph SW | 2% |
| Monday Night | 39°F | Mostly Clear | 5 mph W | 0% |
Forecast source: National Weather Service (api.weather.gov) for Rock Falls (41.772, -89.694). Updated through the day.
Growing snapshot for Rock Falls
Last spring frost
Apr 21
First fall frost
Oct 19
Growing season
180 days
Hardiness zone
5b
More local growing data for Rock Falls: nearby ZIP 61071 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Dixon 1W, Il (12.2 mi from Rock Falls). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.