O'Fallon, Missouri vs Mason Climate
96%matchOn climate, Mason is a 96% match for O'Fallon. Very close: temperatures within 4°F (2°C), with similar rain, humidity and sun.
O'Fallon gets 39 in (998 mm) of rain a year and Mason 43 in (1103 mm). July is the warmest month in both, with highs of 90°F (32°C) in O'Fallon and 86°F (30°C) in Mason.
Climate fingerprints: ring color = average temperature, thickness = rain. January at the top.
Month by month
Highs and lows (°F)
O'FallonMasonsolid = high, dashed = low
Rain (in per month)
O'FallonMason
Monthly averages
| Month | High | Low | Rain | |||
|---|---|---|---|---|---|---|
| O'Fallon | Mason | O'Fallon | Mason | O'Fallon | Mason | |
| Jan | 40°F(5°C) | 38°F(3°C) | 22°F(-6°C) | 21°F(-6°C) | 2.0 in(50 mm) | 3.0 in(77 mm) |
| Feb | 46°F(8°C) | 42°F(6°C) | 25°F(-4°C) | 24°F(-5°C) | 2.0 in(52 mm) | 2.7 in(69 mm) |
| Mar | 57°F(14°C) | 53°F(12°C) | 34°F(1°C) | 32°F(0°C) | 3.2 in(81 mm) | 4.2 in(106 mm) |
| Apr | 69°F(20°C) | 65°F(19°C) | 44°F(7°C) | 42°F(5°C) | 3.9 in(98 mm) | 4.4 in(112 mm) |
| May | 78°F(26°C) | 75°F(24°C) | 55°F(13°C) | 52°F(11°C) | 4.8 in(121 mm) | 4.9 in(124 mm) |
| Jun | 86°F(30°C) | 83°F(28°C) | 64°F(18°C) | 61°F(16°C) | 3.7 in(95 mm) | 4.1 in(103 mm) |
| Jul | 90°F(32°C) | 86°F(30°C) | 68°F(20°C) | 64°F(18°C) | 4.3 in(108 mm) | 4.2 in(107 mm) |
| Aug | 89°F(32°C) | 85°F(30°C) | 66°F(19°C) | 63°F(17°C) | 3.3 in(84 mm) | 3.2 in(82 mm) |
| Sep | 82°F(28°C) | 80°F(27°C) | 57°F(14°C) | 55°F(13°C) | 3.5 in(88 mm) | 3.2 in(82 mm) |
| Oct | 70°F(21°C) | 68°F(20°C) | 45°F(7°C) | 43°F(6°C) | 3.1 in(80 mm) | 3.0 in(77 mm) |
| Nov | 56°F(13°C) | 54°F(12°C) | 35°F(2°C) | 34°F(1°C) | 3.1 in(79 mm) | 3.2 in(82 mm) |
| Dec | 44°F(7°C) | 42°F(6°C) | 26°F(-3°C) | 26°F(-3°C) | 2.4 in(62 mm) | 3.2 in(82 mm) |
1991–2020 averages, by calendar month.