Weather & Climate
Mount Vernon, Illinois, United States
Overview
Available climate summaries for Mount Vernon. Origins and reference periods are unverified; stored values may include AI estimates. Treat these as estimates until independently verified.
Key Metrics
Annual Avg
12.9°C
Summer Avg
24.5°C
Winter Avg
0.4°C
Record High
42.6°C
Record Low
-22.9°C
Annual Precipitation
1123.2 mm
Avg Humidity
77%
Summer Humidity
75%
Winter Humidity
82%
Monthly Averages
| Month | High (°C) | Avg (°C) | Low (°C) | Rain (mm) | Humidity (%) | Sunshine (h) | Wind (kph) |
|---|---|---|---|---|---|---|---|
| Jan | 20.6° | -1° | -22.9° | 68.2 | 82% | 63 | 63.4 |
| Feb | 22.3° | 0.7° | -20.9° | 67.2 | 81% | 78 | 65.3 |
| Mar | 26.4° | 6.8° | -14.9° | 99.5 | 79% | 115 | 59.3 |
| Apr | 29.3° | 13.3° | -5.8° | 118.2 | 77% | 151 | 57.9 |
| May | 31.8° | 18.6° | 1.1° | 122.8 | 79% | 173 | 61.9 |
| Jun | 41.1° | 23.5° | 4.3° | 111.9 | 77% | 194 | 54 |
| Jul | 42.6° | 25.3° | 10.9° | 101.1 | 75% | 195 | 33.4 |
| Aug | 39.6° | 24.7° | 10.4° | 87.4 | 72% | 176 | 40.4 |
| Sep | 36° | 20.9° | 3.6° | 76.5 | 70% | 142 | 60.8 |
| Oct | 33.2° | 13.8° | -3.8° | 100.1 | 72% | 106 | 49.9 |
| Nov | 26.7° | 6.9° | -11.2° | 88.8 | 76% | 71 | 55.4 |
| Dec | 21.5° | 1.4° | -17° | 81.5 | 83% | 54 | 63.4 |
Data sources
Estimates and unverified origins
Oyster List climate data - Climate origins are unverified. Available methods include historical APIs and AI estimates; stored rows do not identify the original dataset, reference period, or model for each value. Treat these summaries as estimates until independently verified. Record updated 2026-03-22.