Weather World
Alton Monthly Climate Averages
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi 31°F Lo 16°F | Hi 32°F Lo 17°F | Hi 39°F Lo 23°F | Hi 47°F Lo 29°F | Hi 57°F Lo 38°F | Hi 72°F Lo 49°F | Hi 76°F Lo 56°F | Hi 73°F Lo 54°F | Hi 66°F Lo 47°F | Hi 53°F Lo 35°F | Hi 42°F Lo 25°F | Hi 32°F Lo 17°F |
| 6 mph | 7 mph | 8 mph | 9 mph | 8 mph | 8 mph | 6 mph | 6 mph | 6 mph | 7 mph | 6 mph | 6 mph |
| 2.3 in | 3.3 in | 3.4 in | 1.8 in | 2 in | 0.9 in | 4 in | 3.9 in | 2.4 in | 2.2 in | 2.7 in | 3.2 in |
| 72% | 72% | 64% | 49% | 40% | 29% | 40% | 44% | 43% | 48% | 55% | 69% |
| 35% | 37% | 34% | 26% | 22% | 13% | 24% | 22% | 17% | 19% | 24% | 35% |
| 30.2 in | 30.1 in | 30.0 in | 29.9 in | 29.9 in | 29.9 in | 29.9 in | 30.0 in | 30.0 in | 30.0 in | 30.1 in | 30.1 in |
| 20 | 15 | 16 | 20 | 24 | 27 | 21 | 21 | 25 | 25 | 22 | 20 |
| 6 | 6 | 7 | 5 | 6 | 3 | 10 | 10 | 5 | 5 | 4 | 5 |
| 6 | 7 | 8 | 4 | 2 | 0 | 0 | 0 | 0 | 1 | 4 | 6 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 2 | 1 | 2 | 2 | 4 | 5 | 5 | 4 | 3 | 2 | 2 | 1 |
| 227 | 193 | 224 | 250 | 252 | 289 | 249 | 275 | 286 | 281 | 271 | 228 |
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi -1°C Lo -9°C | Hi 0°C Lo -8°C | Hi 4°C Lo -5°C | Hi 8°C Lo -1°C | Hi 14°C Lo 3°C | Hi 22°C Lo 9°C | Hi 25°C Lo 13°C | Hi 23°C Lo 12°C | Hi 19°C Lo 8°C | Hi 12°C Lo 2°C | Hi 5°C Lo -4°C | Hi 0°C Lo -8°C |
| 10 km/h | 11 km/h | 12 km/h | 14 km/h | 13 km/h | 13 km/h | 10 km/h | 10 km/h | 10 km/h | 11 km/h | 10 km/h | 10 km/h |
| 59 mm | 84 mm | 87 mm | 45 mm | 51 mm | 23 mm | 100 mm | 98 mm | 61 mm | 56 mm | 68 mm | 82 mm |
| 72% | 72% | 64% | 49% | 40% | 29% | 40% | 44% | 43% | 48% | 55% | 69% |
| 35% | 37% | 34% | 26% | 22% | 13% | 24% | 22% | 17% | 19% | 24% | 35% |
| 1023 mb | 1019 mb | 1016 mb | 1013 mb | 1012 mb | 1012 mb | 1014 mb | 1014 mb | 1015 mb | 1016 mb | 1019 mb | 1021 mb |
| 20 | 15 | 16 | 20 | 24 | 27 | 21 | 21 | 25 | 25 | 22 | 20 |
| 6 | 6 | 7 | 5 | 6 | 3 | 10 | 10 | 5 | 5 | 4 | 5 |
| 6 | 7 | 8 | 4 | 2 | 0 | 0 | 0 | 0 | 1 | 4 | 6 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 2 | 1 | 2 | 2 | 4 | 5 | 5 | 4 | 3 | 2 | 2 | 1 |
| 227 | 193 | 224 | 250 | 252 | 289 | 249 | 275 | 286 | 281 | 271 | 228 |
| Month |
| Avg. Temperatures |
| Avg. Wind Speed |
| Avg. Precipitation |
| Average Humidity |
| Avg. Cloud Cover |
| Pressure Average |
| Average Dry Days |
| Avg. Precip. Days |
| Avg. Snow Days |
| Average Fog Days |
| Average UV Index |
| Avg. Hours of Sun |
Averages are based on historical weather data from the past 10 years.