Decatur (IL) Climate by Month
The temperature in Decatur can vary greatly throughout the year.
The temperatures shift from warm
to cold.
It also has a notably wet climate with much precipitation.
Let's now guide you through the climate details for a complete overview.
Average day and night temperature
Depending on the time of the year, temperatures range from comfortable to chilly in Decatur. Average daytime temperatures range from a comfortable 30°C in July, the warmest time of the year, to a chilly 2°C during cooler months like January. At night, temperatures typically average around -7°C during these months.
The mean minimum and maximum temperatures throughout the year
Precipitation and rainy days
Decatur has a relatively rain/snowy climate with high precipitation levels, averaging 1057 mm of rain/snowfall annually. Significant seasonal changes in precipitation occur throughout the year. During the wetter season, June receives high rainfall, averaging 149 mm of precipitation, recorded across 12 rainy days. In contrast, the drier season, January brings less snow/rainfall, with 43 mm over 8 snowy/rainy days.The mean monthly precipitation over the year, including rain, hail and snow
The average number of days each month with precipitation
Sunshine over the year
Seasonal changes in sunshine hours are quite dramatic in Decatur. While July receives considerable daily sunshine with up to 10.7 hours, December marks the darkest time of the year, where sunshine is scarce with only 4.3 hours of sunlight per day.Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Average humidity
The relative humidity is moderate throughout the year in Decatur.
Relative humidity over the year
The best time of year to visit Decatur in the United States of America
Other facts from our historical weather data:The hottest season / summer takes place in June, July, August and September.
July has an average maximum temperature of 30°C and is the warmest month of the year.
The coldest month is January with an average maximum temperature of 2°C.
June tops the wettest month list with 149 mm of rainfall.
January is the driest month with 43 mm of precipitation.
July is the sunniest month with an average of 320 hours of sunshine.
No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.
