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Climate & Weather Averages in Decatur, Illinois, USA

Currently: -5 °C. Sunny. (Weather station: Decatur Airport, USA). See more current weather

Annual Weather Averages Near Decatur

Averages are for Decatur Airport, which is 8 kilometers from Decatur.

Based on weather reports collected during 1992–2021.

All Year Climate & Weather Averages in Decatur

High Temp: 30 °C

Low Temp: -6 °C

Mean Temp: 12 °C

Precipitation: 78.7 mm

Humidity: 72%

Dew Point: 7 °C

Wind: 26 km/h

Pressure: 1017 mbar

Visibility: 15 km

一月 Climate & Weather Averages in Decatur

High Temp: 2 °C

Low Temp: -6 °C

Mean Temp: -2 °C

Precipitation: 52.4 mm

Humidity: 79%

Dew Point: -6 °C

Wind: 31 km/h

Pressure: 1020 mbar

Visibility: 14 km

二月 Climate & Weather Averages in Decatur

High Temp: 5 °C

Low Temp: -5 °C

Mean Temp: 0 °C

Precipitation: 46.7 mm

Humidity: 76%

Dew Point: -4 °C

Wind: 31 km/h

Pressure: 1020 mbar

Visibility: 14 km

三月 Climate & Weather Averages in Decatur

High Temp: 11 °C

Low Temp: 0 °C

Mean Temp: 6 °C

Precipitation: 65.3 mm

Humidity: 70%

Dew Point: 0 °C

Wind: 31 km/h

Pressure: 1019 mbar

Visibility: 15 km

四月 Climate & Weather Averages in Decatur

High Temp: 18 °C

Low Temp: 6 °C

Mean Temp: 12 °C

Precipitation: 92.9 mm

Humidity: 66%

Dew Point: 5 °C

Wind: 32 km/h

Pressure: 1015 mbar

Visibility: 16 km

五月 Climate & Weather Averages in Decatur

High Temp: 24 °C

Low Temp: 12 °C

Mean Temp: 18 °C

Precipitation: 107.6 mm

Humidity: 68%

Dew Point: 12 °C

Wind: 27 km/h

Pressure: 1015 mbar

Visibility: 16 km

六月 Climate & Weather Averages in Decatur

High Temp: 29 °C

Low Temp: 17 °C

Mean Temp: 23 °C

Precipitation: 113.8 mm

Humidity: 70%

Dew Point: 17 °C

Wind: 22 km/h

Pressure: 1014 mbar

Visibility: 16 km

七月 Climate & Weather Averages in Decatur

High Temp: 30 °C

Low Temp: 19 °C

Mean Temp: 24 °C

Precipitation: 98.3 mm

Humidity: 73%

Dew Point: 19 °C

Wind: 18 km/h

Pressure: 1015 mbar

Visibility: 15 km

八月 Climate & Weather Averages in Decatur

High Temp: 29 °C

Low Temp: 17 °C

Mean Temp: 23 °C

Precipitation: 77.5 mm

Humidity: 74%

Dew Point: 18 °C

Wind: 17 km/h

Pressure: 1016 mbar

Visibility: 15 km

九月 Climate & Weather Averages in Decatur

High Temp: 27 °C

Low Temp: 13 °C

Mean Temp: 20 °C

Precipitation: 76.9 mm

Humidity: 69%

Dew Point: 13 °C

Wind: 19 km/h

Pressure: 1017 mbar

Visibility: 16 km

十月 Climate & Weather Averages in Decatur

High Temp: 19 °C

Low Temp: 7 °C

Mean Temp: 13 °C

Precipitation: 80.1 mm

Humidity: 69%

Dew Point: 7 °C

Wind: 25 km/h

Pressure: 1018 mbar

Visibility: 16 km

十一月 Climate & Weather Averages in Decatur

High Temp: 11 °C

Low Temp: 1 °C

Mean Temp: 6 °C

Precipitation: 75.8 mm

Humidity: 73%

Dew Point: 1 °C

Wind: 29 km/h

Pressure: 1020 mbar

Visibility: 15 km

十二月 Climate & Weather Averages in Decatur

High Temp: 5 °C

Low Temp: -4 °C

Mean Temp: 1 °C

Precipitation: 57.4 mm

Humidity: 79%

Dew Point: -3 °C

Wind: 28 km/h

Pressure: 1020 mbar

Visibility: 14 km

Quick Climate Info

Hottest Month七月 (24 °C avg)
Coldest Month一月 (-2 °C avg)
Wettest Month六月 (113.8 mm avg)
Windiest Month四月 (32 km/h avg)
Annual precip.944.7 mm (per year)

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