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Round Lake, IL Weather & Growing Conditions

Overnight
61°F
Showers And Thunderstorms
Showers and thunderstorms. Some of the storms could produce heavy rain. Cloudy. Low around 61, with temperatures rising to around 64 overnight. East southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

7-day forecast

WhenTempForecastWindPrecip
Overnight 61°F Showers And Thunderstorms 10 mph ESE 100%
Saturday 75°F Showers And Thunderstorms then Showers And Thunderstorms Likely 5 to 10 mph SSE 100%
Saturday Night 60°F Showers And Thunderstorms 5 to 10 mph ENE 94%
Sunday 68°F Chance Showers And Thunderstorms 10 to 20 mph NNE 52%
Sunday Night 54°F Mostly Cloudy 15 mph NE 13%
Monday 63°F Slight Chance Rain Showers 15 mph ENE 23%
Monday Night 50°F Mostly Cloudy 10 to 15 mph ENE 14%
Tuesday 62°F Mostly Cloudy 10 to 15 mph NE 12%
Tuesday Night 50°F Mostly Cloudy 5 to 15 mph NE 6%
Wednesday 64°F Partly Sunny 5 to 10 mph NE 11%
Wednesday Night 51°F Mostly Cloudy 0 to 10 mph NNE 4%
Thursday 66°F Partly Sunny 5 mph NNE 5%
Thursday Night 51°F Mostly Cloudy 0 to 5 mph NNE 4%
Friday 69°F Mostly Sunny 0 to 5 mph NE 5%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Round Lake, IL

Last spring frost
Apr 24
First fall frost
Oct 23
Growing season
180 days
Hardiness zone
5b

Explore more for Round Lake, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Lake Villa 2Ne, Il (5.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.