All Countries
Weather & Climate in Raritan, IL
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Raritan experiences four distinct seasons with an average annual temperature of 51°F (10°C). Winters average 23°F in January while summers reach 75°F in July. The area gets 275 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 39.1 inches. Air quality is rated Good with a median AQI of 43. The city sits at an elevation of 760 feet.
Temperature
23°F Jan (-5°C)
75°F Jul (24°C)
| Annual Average | 50.8°F |
| 6% below US avg | |
| January Average | 23°F (-5°C) |
| July Average | 75°F (24°C) |
| Sunny Days | 275 days/yr |
Geography
| Elevation | 760 ft (232 m) |
| Area | 0.0 sq mi (0.1 km²) |
| Population Density | 1,550/sq mi |
| Coordinates | 40.6958°N, 90.8251°W |
| Timezone | America/Chicago |
| County | Henderson County County |
| Nearest Airport | Southeast Iowa Regional (BRL) 17 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 17.5 / 100 |
| Social Vulnerability | 77.1 / 100 |
| Community Resilience | 37.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Very Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Low |
| Winter Weather | Very Low |
| Lightning | Relatively Low |
| Ice Storm | Relatively Low |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tornado History
574 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 10 fatalities, 475 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 13, 1995 | EF4 | 57 km | 7.0 mi | 0 |
| May 13, 1995 | EF4 | 43 km | 50.0 mi | 0 |
| Jun 29, 1976 | EF4 | 91 km | 4.9 mi | 0 |
| Apr 4, 2023 | EF3 | 59 km | 19.9 mi | 0 |
| May 27, 2019 | EF3 | 99 km | 7.3 mi | 0 |
| Jun 1, 2007 | EF3 | 71 km | 15.8 mi | 0 |
| May 10, 2003 | EF3 | 100 km | 17.5 mi | 0 |
| Apr 8, 1999 | EF3 | 65 km | 7.5 mi | 0 |
| May 15, 1998 | EF3 | 100 km | 47.0 mi | 0 |
| May 13, 1995 | EF3 | 82 km | 25.0 mi | 0 |
| May 9, 1995 | EF3 | 98 km | 10.0 mi | 0 |
| Jun 21, 1981 | EF3 | 54 km | 8.8 mi | 1 |
| Aug 15, 1978 | EF3 | 64 km | 6.4 mi | 0 |
| Jul 23, 1975 | EF3 | 56 km | 14.0 mi | 2 |
| Jul 23, 1975 | EF3 | 45 km | 11.1 mi | 0 |
| Jun 13, 1975 | EF3 | 49 km | 6.6 mi | 0 |
| Jun 14, 1974 | EF3 | 77 km | 48.6 mi | 0 |
| Apr 13, 1974 | EF3 | 73 km | 11.0 mi | 0 |
| Sep 30, 1973 | EF3 | 53 km | 0.1 mi | 0 |
| May 1, 1973 | EF3 | 82 km | 3.6 mi | 2 |
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 | 52 km |
| 2002 | HSB 03 2 | 1,130 | 52 km |
| 2000 | DESTRUST A | 756 | 53 km |
| 2006 | HSB 003 | 674 | 51 km |
| 2004 | HSB 009 | 608 | 52 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 23°F (-5°C) | 1.5 in | Coldest |
| February | 28°F (-3°C) | 1.4 in | Driest |
| March | 39°F (4°C) | 2.8 in | |
| April | 52°F (11°C) | 3.8 in | |
| May | 63°F (17°C) | 4.1 in | |
| June | 72°F (22°C) | 4.1 in | |
| July | 75°F (24°C) | 4.3 in | Warmest, Wettest |
| August | 73°F (23°C) | 3.7 in | |
| September | 65°F (19°C) | 4.0 in | |
| October | 54°F (12°C) | 2.9 in | |
| November | 40°F (4°C) | 2.6 in | |
| December | 27°F (-3°C) | 2.1 in |
Raritan has a seasonal temperature swing of 51°F / from 23°F in January to 75°F in July. Total annual precipitation is 37.3 inches, with July being the wettest month (4.3") and February the driest (1.4").