ClimateAverages

Mount Prospect Climate

Illinois, United States of America · population 54,747 · 383 weather stations within 200 km · records 1777 to 2025

Average annual daytime high
14.3°C
Warmest month · July
28.0°C
Typical daytime high
Coldest month · January
-10.1°C
Typical overnight low

Mount Prospect has an average annual daytime high of 14.3°C, based on the 1951 to 1980 baseline. Its warmest month is July, when highs typically reach 28.0°C, and its coldest is January, with overnight lows near -10.1°C.

Month by month averages

MonthAvg highAvg low
January-1.7°C-10.1°CColdest
February0.9°C-7.6°C
March6.3°C-2.6°C
April14.1°C3.4°C
May20.4°C8.8°C
June25.8°C14.3°C
July28.0°C17.1°CWarmest
August27.2°C16.6°C
September23.4°C12.4°C
October16.9°C6.2°C
November8.5°C-0.2°C
December1.3°C-6.4°C

Temperature range across the year

-12°-2°9°19°30°JanFebMarAprMayJunJulAugSepOctNovDec
Daytime high Overnight low
Hottest year on record
2011
+2.8°C vs. 1951–1980
Coldest year on record
1842
-2.7°C vs. 1951–1980

These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.

Is Mount Prospect getting hotter?

Since 1900, Mount Prospect's average temperature has risen by +2.3°C. Compared to the earliest station records that begin in 1777, warming totals +2.4°C.

8.5°9.2°9.9°10.6°11.3°1951–1980 baseline190019251950197520002025

20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.

Best time to visit
May to October

Daytime highs sit within a comfortable 15°C to 26°C range.

FAQ

What is the average temperature in Mount Prospect?

Mount Prospect's average annual daytime high is 14.3°C, based on the 1951 to 1980 baseline period. The warmest month is July, with highs averaging 28.0°C, and the coldest is January, with lows averaging -10.1°C.

What is the warmest month in Mount Prospect?

July is the warmest month in Mount Prospect, with typical daytime highs of 28.0°C.

What is the hottest year on record for Mount Prospect?

2011 is the hottest year on record for Mount Prospect, running +2.8°C above the 1951 to 1980 baseline.

Is Mount Prospect getting hotter?

Yes. Since 1900, Mount Prospect has warmed by roughly +2.3°C.

When is the best time to visit Mount Prospect?

May to October typically offers the most comfortable daytime highs, in the 15°C to 26°C range.

Nearby cities

Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.