Potomac, IL
Climate overview — based on NOAA 1991-2020 normals from HOOPESTON, IL US.
Year-round temperatures (°F)
Climate summary
Potomac has an annual average temperature of 52.3°F with about 40.9 inches of precipitation per year and 20.3 inches of snow. The warmest month is July (average high 84.8°F), and the coldest is January (average low 18.3°F). June is typically the wettest month (4.89 in) and February the driest (1.96 in). Snow typically falls from November through April.
Best time to visit Potomac
Full guide →Climate change signal
All-time records →20 of 366 (5.5%) of Potomac's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1900s | 14 | |
| 1910s | 52 | |
| 1920s | 39 | |
| 1930s | 107 | |
| 1940s | 20 | |
| 1950s | 40 | |
| 1960s | 5 | |
| 1970s | 13 | |
| 1980s | 18 | |
| 1990s | 11 | |
| 2000s | 15 | |
| 2010s | 18 | |
| 2020s | 14 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 33.5°F | 18.3°F | 25.9°F | 2.12 in | 6.5 in | 9 |
| February | 38.3°F | 21.7°F | 30.0°F | 1.96 in | 5.2 in | 8 |
| March | 50.4°F | 30.9°F | 40.7°F | 2.82 in | 2.2 in | 9 |
| April | 63.9°F | 41.3°F | 52.6°F | 3.95 in | 0.4 in | 11 |
| May | 74.3°F | 52.5°F | 63.4°F | 4.78 in | — | 11 |
| June | 82.7°F | 61.7°F | 72.2°F | 4.89 in | — | 10 |
| July | 84.8°F | 64.5°F | 74.7°F | 4.59 in | — | 9 |
| August | 83.4°F | 62.5°F | 72.9°F | 3.96 in | — | 8 |
| September | 78.6°F | 55.2°F | 66.9°F | 3.36 in | — | 8 |
| October | 65.6°F | 44.4°F | 55.0°F | 3.43 in | 0.1 in | 9 |
| November | 50.4°F | 33.2°F | 41.8°F | 2.91 in | 0.6 in | 9 |
| December | 38.1°F | 23.9°F | 31.0°F | 2.12 in | 5.3 in | 8 |
Climate twins of Potomac
Why these? →The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).