Weather & Climate in Hamilton, IL
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Hamilton experiences four distinct seasons with an average annual temperature of 52°F (11°C). Winters average 25°F in January while summers reach 76°F in July. Annual precipitation totals 39.8 inches. The area receives 21.5 inches of snow annually, a moderate snowfall amount. The city sits at an elevation of 497 feet.
Temperature
25°F Jan (-4°C)
76°F Jul (25°C)
| Annual Average | 52.1°F |
| 4% below US avg | |
| January Average | 25°F (-4°C) |
| July Average | 76°F (25°C) |
Geography
| Elevation | 497 ft (151 m) |
| Area | 3.6 sq mi (9.2 km²) |
| Population Density | 769/sq mi |
| Coordinates | 40.3915°N, 91.3613°W |
| Timezone | America/Chicago |
| County | Hancock County County |
| Nearest Airport | Southeast Iowa Regional (BRL) 30 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 31.1 / 100 |
| Social Vulnerability | 64.8 / 100 |
| Community Resilience | 61.4 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Very Low |
| Hail | Relatively Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Low |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Low |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Moderate |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
1 earthquake (M2.5+) recorded within 150 km since 1990. Strongest on record: M2.9.
| Feb 8, 2004 | 6 km SSW of Stoutsville, Missouri | M2.9 | 109 km | 5 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
444 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 7 fatalities, 254 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 13, 1995 | EF4 | 21 km | 50.0 mi | 0 |
| May 13, 1995 | EF4 | 90 km | 7.0 mi | 0 |
| Jan 24, 1967 | EF4 | 99 km | 25.7 mi | 0 |
| Apr 4, 2023 | EF3 | 88 km | 19.9 mi | 0 |
| May 27, 2019 | EF3 | 62 km | 7.3 mi | 0 |
| Jun 1, 2007 | EF3 | 99 km | 15.8 mi | 0 |
| May 10, 2003 | EF3 | 86 km | 12.0 mi | 0 |
| Apr 8, 1999 | EF3 | 98 km | 16.0 mi | 0 |
| Apr 8, 1999 | EF3 | 9 km | 7.5 mi | 0 |
| Jun 21, 1981 | EF3 | 65 km | 8.8 mi | 1 |
| Jul 23, 1975 | EF3 | 89 km | 11.1 mi | 0 |
| Jun 13, 1975 | EF3 | 99 km | 6.6 mi | 0 |
| Apr 13, 1974 | EF3 | 95 km | 0.1 mi | 0 |
| Apr 13, 1974 | EF3 | 17 km | 11.0 mi | 0 |
| Sep 30, 1973 | EF3 | 41 km | 0.1 mi | 0 |
| May 1, 1973 | EF3 | 31 km | 3.6 mi | 2 |
| Apr 20, 1973 | EF3 | 59 km | 9.5 mi | 0 |
| Apr 21, 1967 | EF3 | 83 km | 0.1 mi | 0 |
| Apr 16, 1967 | EF3 | 71 km | 19.4 mi | 2 |
| Jan 24, 1967 | EF3 | 81 km | 25.0 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Wildfire History
5 wildfires (100+ acres) recorded within 100 km. Largest: UNIT 3 (1,206 acres, 1999).
| Year | Name | Acres Burned | Distance |
| 1999 | UNIT 3 | 1,206 | 83 km |
| 2002 | HSB 03 2 | 1,130 | 84 km |
| 2000 | DESTRUST A | 756 | 84 km |
| 2006 | HSB 003 | 674 | 83 km |
| 2004 | HSB 009 | 608 | 84 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 25°F (-4°C) | 1.6 in | Coldest, Driest |
| February | 29°F (-2°C) | 1.8 in | |
| March | 40°F (5°C) | 2.5 in | |
| April | 52°F (11°C) | 4.2 in | |
| May | 63°F (17°C) | 5.3 in | Wettest |
| June | 72°F (22°C) | 5.2 in | |
| July | 76°F (25°C) | 4.1 in | Warmest |
| August | 74°F (24°C) | 3.8 in | |
| September | 67°F (19°C) | 3.4 in | |
| October | 55°F (13°C) | 3.3 in | |
| November | 42°F (5°C) | 2.6 in | |
| December | 30°F (-1°C) | 2.0 in |
Hamilton has a seasonal temperature swing of 51°F / from 25°F in January to 76°F in July. Total annual precipitation is 39.8 inches, with May being the wettest month (5.3") and January the driest (1.6").