Glen Ellyn, IL Weather & Climate Normals
Glen Ellyn's real weather, in one number
Glen Ellyn, IL scores 45/100 on this site's reading of NOAA's own 30-year normals: strongly seasonal. Comfortable weather is limited to a shorter window; summers, winters, or precipitation swing wide. 5 of the year's 12 months average between 55 and 75°F, the range this site counts as mild.
Glen Ellyn's hottest and coldest months
Glen Ellyn's hottest month is Jul, averaging 74°F; its coldest is Jan, averaging 25°F, a 49.5°F swing across the year, one of the widest gaps in this dataset.
Glen Ellyn's weather across the year
| Month | Avg high | Avg low | Precip | Snow |
|---|---|---|---|---|
| Jan | 33°F | 17°F | 2.12in | 9.3in |
| Feb | 38°F | 20°F | 1.96in | 5.1in |
| Mar | 50°F | 29°F | 2.46in | 4.5in |
| Apr | 63°F | 38°F | 4.1in | 0.3in |
| May | 74°F | 49°F | 4.46in | 0in |
| Jun | 83°F | 59°F | 4.65in | 0in |
| Jul | 86°F | 63°F | 3.86in | 0in |
| Aug | 84°F | 62°F | 4.4in | 0in |
| Sep | 78°F | 54°F | 3.3in | 0in |
| Oct | 65°F | 43°F | 3.56in | 0in |
| Nov | 50°F | 32°F | 2.81in | 0.9in |
| Dec | 38°F | 23°F | 2.22in | 4.2in |
May, Jun, Jul, Aug, and Sep are the best time to see Glen Ellyn at its mildest; the rest of the year, plan around Jan's cold.
Rain and snow in Glen Ellyn
Glen Ellyn averages 39.9in of precipitation a year across roughly 116 days with measurable rain or snow, and 24.3in of snow a year.
Where Glen Ellyn ranks
Glen Ellyn ranks 3291 of 4876 US cities in this dataset for comfort score, and 121 of 330 within IL. About 28,872 people live there.
If you need tomorrow's forecast, not the 30-year average
Everything above is a 30-year average from Wheaton 3 Se, IL US, 3.8 miles from Glen Ellyn, not a prediction for any specific day.
More on how this is worked out
How the comfort score is calculated · Why some cities show no snow or rain figure