Olney, IL Weather & Climate Normals
Olney's real weather, in one number
Olney, IL scores 48/100 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.
Olney's hottest and coldest months
Olney's hottest month is Jul, averaging 76°F; its coldest is Jan, averaging 29°F, a 46.9°F swing across the year, one of the widest gaps in this dataset.
Olney's weather across the year
| Month | Avg high | Avg low | Precip | Snow |
|---|---|---|---|---|
| Jan | 38°F | 21°F | 3.52in | 3.6in |
| Feb | 43°F | 24°F | 2.57in | 2.6in |
| Mar | 53°F | 32°F | 4.21in | 1.1in |
| Apr | 66°F | 43°F | 5.02in | 0in |
| May | 75°F | 53°F | 5.6in | 0in |
| Jun | 84°F | 62°F | 4.79in | 0in |
| Jul | 87°F | 66°F | 4.96in | 0in |
| Aug | 86°F | 64°F | 3.19in | 0in |
| Sep | 80°F | 56°F | 3.31in | 0in |
| Oct | 69°F | 44°F | 3.83in | 0in |
| Nov | 54°F | 34°F | 4.26in | 0.5in |
| Dec | 42°F | 26°F | 3.5in | 2.7in |
May, Jun, Aug, Sep, and Oct are the best time to see Olney at its mildest; the rest of the year, plan around Jul's heat and Jan's cold.
Rain and snow in Olney
Olney averages 48.76in of precipitation a year across roughly 120 days with measurable rain or snow, and 10.5in of snow a year.
Where Olney ranks
Olney ranks 2456 of 4876 US cities in this dataset for comfort score, and 70 of 330 within IL. About 8,431 people live there.
If you need tomorrow's forecast, not the 30-year average
Everything above is a 30-year average from Olney 2s, IL US, 1.9 miles from Olney, not a prediction for any specific day.
More on how this is worked out
What a 30-year climate normal actually is · Why this uses the nearest NOAA station