Weather World
Mercer County, IL Official Website
Mercer County Monthly Climate Averages
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi 30°F Lo 17°F | Hi 35°F Lo 20°F | Hi 49°F Lo 33°F | Hi 60°F Lo 42°F | Hi 71°F Lo 54°F | Hi 80°F Lo 63°F | Hi 83°F Lo 66°F | Hi 82°F Lo 64°F | Hi 77°F Lo 58°F | Hi 63°F Lo 46°F | Hi 49°F Lo 34°F | Hi 37°F Lo 25°F |
| 10 mph | 10 mph | 11 mph | 11 mph | 9 mph | 8 mph | 7 mph | 7 mph | 8 mph | 10 mph | 10 mph | 10 mph |
| 1.9 in | 2 in | 3.8 in | 5 in | 6 in | 6.1 in | 4.5 in | 4 in | 3.4 in | 3.4 in | 3.2 in | 2.5 in |
| 82% | 80% | 74% | 73% | 77% | 80% | 82% | 78% | 72% | 68% | 72% | 79% |
| 56% | 53% | 50% | 48% | 44% | 34% | 33% | 30% | 28% | 38% | 41% | 54% |
| 30.1 in | 30.1 in | 30.0 in | 29.9 in | 29.9 in | 29.9 in | 30.0 in | 30.0 in | 30.0 in | 30.0 in | 30.1 in | 30.1 in |
| 19 | 18 | 22 | 21 | 21 | 21 | 25 | 25 | 25 | 25 | 25 | 23 |
| 7 | 6 | 7 | 8 | 10 | 9 | 6 | 6 | 5 | 6 | 5 | 6 |
| 5 | 4 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 3 |
| 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
| 1 | 2 | 2 | 4 | 5 | 5 | 6 | 5 | 4 | 2 | 1 | 1 |
| 130 | 132 | 154 | 151 | 174 | 213 | 231 | 237 | 244 | 194 | 188 | 145 |
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi -1°C Lo -9°C | Hi 2°C Lo -7°C | Hi 9°C Lo 1°C | Hi 15°C Lo 6°C | Hi 21°C Lo 12°C | Hi 27°C Lo 17°C | Hi 28°C Lo 19°C | Hi 28°C Lo 18°C | Hi 25°C Lo 14°C | Hi 17°C Lo 8°C | Hi 9°C Lo 1°C | Hi 3°C Lo -4°C |
| 16 km/h | 17 km/h | 17 km/h | 17 km/h | 15 km/h | 13 km/h | 11 km/h | 11 km/h | 13 km/h | 16 km/h | 17 km/h | 16 km/h |
| 48 mm | 51 mm | 96 mm | 128 mm | 152 mm | 155 mm | 115 mm | 102 mm | 86 mm | 87 mm | 80 mm | 64 mm |
| 82% | 80% | 74% | 73% | 77% | 80% | 82% | 78% | 72% | 68% | 72% | 79% |
| 56% | 53% | 50% | 48% | 44% | 34% | 33% | 30% | 28% | 38% | 41% | 54% |
| 1021 mb | 1020 mb | 1017 mb | 1014 mb | 1014 mb | 1013 mb | 1014 mb | 1015 mb | 1016 mb | 1016 mb | 1019 mb | 1019 mb |
| 19 | 18 | 22 | 21 | 21 | 21 | 25 | 25 | 25 | 25 | 25 | 23 |
| 7 | 6 | 7 | 8 | 10 | 9 | 6 | 6 | 5 | 6 | 5 | 6 |
| 5 | 4 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 3 |
| 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
| 1 | 2 | 2 | 4 | 5 | 5 | 6 | 5 | 4 | 2 | 1 | 1 |
| 130 | 132 | 154 | 151 | 174 | 213 | 231 | 237 | 244 | 194 | 188 | 145 |
| 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.