Rock Falls, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Rock Falls, a city in Whiteside County, Illinois.
Today
87°F
Mostly Sunny
Mostly sunny. High near 87, with temperatures falling to around 85 in the afternoon. Southwest wind 5 to 10 mph.
7-day forecast for Rock Falls
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 87°F | Mostly Sunny | 5 to 10 mph SW | 4% |
| Tonight | 67°F | Showers And Thunderstorms Likely | 0 to 5 mph W | 81% |
| Wednesday | 78°F | Showers And Thunderstorms then Chance Showers And Thunderstorms | 0 to 5 mph W | 80% |
| Wednesday Night | 62°F | Showers And Thunderstorms | 0 to 5 mph N | 80% |
| Thursday | 80°F | Chance Rain Showers | 0 to 5 mph NE | 44% |
| Thursday Night | 61°F | Mostly Clear | 0 mph | 13% |
| Friday | 82°F | Mostly Sunny | 0 to 5 mph SE | 5% |
| Friday Night | 64°F | Mostly Clear | 0 mph | 8% |
| Saturday | 85°F | Sunny | 0 to 10 mph S | 9% |
| Saturday Night | 70°F | Mostly Clear then Slight Chance Showers And Thunderstorms | 5 mph S | 19% |
| Sunday | 88°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 10 to 15 mph SW | 19% |
| Sunday Night | 69°F | Chance Showers And Thunderstorms | 5 to 10 mph S | 36% |
| Monday | 87°F | Chance Showers And Thunderstorms | 5 to 10 mph S | 36% |
| Monday Night | 70°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 to 10 mph W | 40% |
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 Aug 4, 2026.