Harman US

Allerton, IL Weather & Growing Conditions

Today
88°F
Showers And Thunderstorms then Chance Showers And Thunderstorms
Showers and thunderstorms before noon, then a chance of showers and thunderstorms between noon and 1pm, then a chance of showers and thunderstorms between 1pm and 2pm, then a slight chance of showers and thunderstorms between 2pm and 3pm. Mostly cloudy, with a high near 88. South southwest wind around 7 mph. Chance of precipitation is 80%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 88°F Showers And Thunderstorms then Chance Showers And Thunderstorms 7 mph SSW 79%
Tonight 69°F Mostly Cloudy then Slight Chance Showers And Thunderstorms 6 mph S 15%
Sunday 83°F Chance Showers And Thunderstorms 3 to 10 mph N 54%
Sunday Night 59°F Showers And Thunderstorms Likely then Chance Showers And Thunderstorms 14 mph NE 63%
Monday 69°F Showers And Thunderstorms Likely 13 to 16 mph NE 71%
Monday Night 54°F Chance Rain Showers 12 to 17 mph NE 51%
Tuesday 67°F Chance Showers And Thunderstorms 14 mph NE 28%
Tuesday Night 52°F Chance Showers And Thunderstorms then Mostly Cloudy 8 to 14 mph NNE 28%
Wednesday 70°F Mostly Sunny 10 mph NNE 6%
Wednesday Night 53°F Partly Cloudy 5 to 9 mph NNE 6%
Thursday 71°F Partly Sunny 8 mph NNE 2%
Thursday Night 54°F Partly Cloudy 7 mph NNE 2%
Friday 74°F Mostly Sunny 6 to 9 mph NNE 2%
Friday Night 53°F Partly Cloudy 5 to 8 mph NE 2%

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

Growing snapshot for Allerton, IL

Last spring frost
Apr 19
First fall frost
Oct 19
Growing season
181 days
Hardiness zone
6a

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

Climate data from the nearest NOAA station, Sidell 4N, Il (6.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.