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Altona, IL Weather & Growing Conditions

This Afternoon
82°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms. Mostly cloudy, with a high near 82. South southeast wind around 10 mph, with gusts as high as 17 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
This Afternoon 82°F Slight Chance Showers And Thunderstorms 10 mph SSE 21%
Tonight 66°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 6 mph ESE 71%
Sunday 72°F Showers And Thunderstorms Likely 5 to 14 mph NNE 70%
Sunday Night 57°F Chance Showers And Thunderstorms 14 mph NE 51%
Monday 63°F Rain Showers Likely 13 to 16 mph ENE 70%
Monday Night 54°F Rain Showers Likely 12 to 15 mph ENE 65%
Tuesday 62°F Rain Showers Likely 14 mph NE 56%
Tuesday Night 50°F Mostly Cloudy 6 to 14 mph NNE 8%
Wednesday 64°F Partly Sunny 10 mph NNE 3%
Wednesday Night 52°F Partly Cloudy 2 to 8 mph NNE 1%
Thursday 68°F Partly Sunny 3 to 7 mph NE 3%
Thursday Night 56°F Slight Chance Rain Showers 1 to 5 mph NE 15%
Friday 72°F Partly Sunny 2 to 7 mph NE 11%
Friday Night 55°F Partly Cloudy 5 mph ENE 6%

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

Growing snapshot for Altona, IL

Last spring frost
Apr 28
First fall frost
Oct 12
Growing season
165 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Altona, Il (0.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.