Marion (IL) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Marion.
Climate overview of Marion
Temperatures in Marion, Illinois, United States of America, vary greatly throughout the year. July is the hottest month at 31°C (88°F), while January is the coldest at 5°C (41°F).
Rain/snowfall is high, totalling around 1246 mm (49 in) per year. April is the wettest month and January the driest.
Marion Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Marion — and find the best time to visit.
Monthly Temperature in Marion
The climate in Marion is known for significant temperature differences throughout the year, making the weather dynamic. Average maximum daytime temperatures range from a very warm 31°C (88°F) in July, the warmest time of the year, to a chilly 5°C (41°F) during cooler months like January.
At night, you can expect temperatures ranging from 20°C (68°F) in July to around -4°C (25°F) during January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Marion
Marion has a notably wet climate with abundant precipitation, recording 1246 mm (49 in) of rain/snowfall per year. While rainfall varies throughout the year, each season offers its own charm. April brings wetter days averaging 149 mm (5.9 in) of precipitation, spread over 11 rainy days.
In contrast, the driest month January experiences a drier climate, with about 72 mm (2.8 in) of snow/rainfall spread across 8 snowy/rainy days. For more details, please visit our Marion Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Best Time to Visit Marion
Frequently asked questions about the climate in Marion
What is the best time to visit Marion?
September and October typically offer the most optimal weather in Marion. In contrast, January, February and December tend to have less optimal conditions.
What temperatures can I expect in Marion?
Daytime highs range from 5°C (41°F) in January to 31°C (88°F) in July. Nighttime lows range from -4°C (25°F) to 20°C (68°F). Temperatures vary considerably through the year.
How much rain does Marion get?
Annual rainfall is around 1246 mm (49 in). April is the wettest month with 149 mm (5.9 in), while January is the driest with 72 mm (2.8 in).
Marion 3-Day Forecast
Marion (IL) 3-Day Forecast
Marion on the map
Marion is highlighted — select any city to see its climate.
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