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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

WhenTempForecastWindPrecip
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

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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.