All Countries
Weather & Climate in Jacksonville, IL
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Jacksonville experiences four distinct seasons with an average annual temperature of 53°F (12°C). Winters average 26°F in January while summers reach 76°F in July. The area gets 293 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 41.4 inches. Air quality is rated Good with a median AQI of 43. The city sits at an elevation of 585 feet.
Temperature
26°F Jan (-3°C)
76°F Jul (25°C)
| Annual Average | 52.8°F |
| 2% below US avg | |
| January Average | 26°F (-3°C) |
| July Average | 76°F (25°C) |
| Sunny Days | 293 days/yr |
Geography
| Elevation | 585 ft (178 m) |
| Area | 4.1 sq mi (10.6 km²) |
| Population Density | 1,656/sq mi |
| Coordinates | 39.7292°N, 90.2322°W |
| Timezone | America/Chicago |
| County | Morgan County County |
| Nearest Airport | Quincy Regional-Baldwin Field (UIN) 53 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 71.1 / 100 |
| Social Vulnerability | 46.0 / 100 |
| Community Resilience | 78.2 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Low |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Low |
| Lightning | Relatively Low |
| Ice Storm | Relatively Low |
| Drought | Relatively High |
| Cold Wave | Relatively High |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
11 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M3.4.
| Mar 2, 1990 | 9 km NW of Vernon, Illinois | M3.4 | 134 km | 0 km |
| Jan 29, 1993 | 7 km WNW of Brownstown, Illinois | M3.2 | 129 km | 5 km |
| Jul 1, 2017 | 9 km SSE of Mulberry Grove, Illinois | M3.1 | 131 km | 17 km |
| Feb 8, 2004 | 6 km SSW of Stoutsville, Missouri | M2.9 | 144 km | 5 km |
| Sep 5, 2004 | 3 km WNW of Saint Peter, Illinois | M2.9 | 149 km | 33 km |
| Apr 29, 2022 | 1 km SSW of Peerless Park, Missouri | M2.8 | 135 km | 8 km |
| Mar 28, 2024 | 1 km NNE of Germantown, Illinois | M2.8 | 142 km | 24 km |
| May 5, 2008 | 3 km SSE of Fenton, Missouri | M2.8 | 139 km | 19 km |
| Sep 5, 2015 | 5 km SE of High Ridge, Missouri | M2.7 | 146 km | 8 km |
| Sep 19, 2024 | 1 km S of Old Monroe, Missouri | M2.6 | 101 km | 2 km |
| Jan 15, 1998 | 1 km SSE of Fenton, Missouri | M2.5 | 138 km | 16 km |
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
594 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 16 fatalities, 630 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 13, 1995 | EF4 | 72 km | 7.0 mi | 0 |
| Jun 14, 1957 | EF4 | 46 km | 4.3 mi | 2 |
| Apr 4, 2023 | EF3 | 67 km | 19.9 mi | 0 |
| Dec 1, 2018 | EF3 | 80 km | 12.5 mi | 0 |
| Apr 19, 2011 | EF3 | 47 km | 4.3 mi | 0 |
| Dec 31, 2010 | EF3 | 43 km | 3.6 mi | 0 |
| Aug 19, 2009 | EF3 | 63 km | 24.3 mi | 0 |
| May 10, 2003 | EF3 | 95 km | 17.5 mi | 0 |
| Jun 1, 1999 | EF3 | 66 km | 10.0 mi | 1 |
| Apr 19, 1996 | EF3 | 91 km | 14.5 mi | 0 |
| Apr 19, 1996 | EF3 | 100 km | 9.4 mi | 0 |
| May 13, 1995 | EF3 | 81 km | 25.0 mi | 0 |
| May 9, 1995 | EF3 | 46 km | 50.0 mi | 0 |
| May 1, 1983 | EF3 | 48 km | 4.0 mi | 0 |
| Jun 21, 1981 | EF3 | 65 km | 8.8 mi | 1 |
| Jul 26, 1978 | EF3 | 39 km | 8.9 mi | 0 |
| Aug 6, 1977 | EF3 | 45 km | 4.1 mi | 0 |
| Mar 20, 1976 | EF3 | 59 km | 8.8 mi | 0 |
| Jul 23, 1975 | EF3 | 94 km | 14.0 mi | 2 |
| Jul 23, 1975 | EF3 | 92 km | 11.1 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 26°F (-3°C) | 1.4 in | Coldest, Driest |
| February | 30°F (-1°C) | 1.7 in | |
| March | 42°F (5°C) | 3.2 in | |
| April | 53°F (12°C) | 3.8 in | |
| May | 63°F (17°C) | 4.7 in | Wettest |
| June | 72°F (22°C) | 4.0 in | |
| July | 76°F (25°C) | 3.7 in | Warmest |
| August | 74°F (23°C) | 3.4 in | |
| September | 67°F (19°C) | 3.5 in | |
| October | 55°F (13°C) | 2.8 in | |
| November | 42°F (6°C) | 3.3 in | |
| December | 31°F (-1°C) | 2.6 in |
Jacksonville has a seasonal temperature swing of 50°F / from 26°F in January to 76°F in July. Total annual precipitation is 38.0 inches, with May being the wettest month (4.7") and January the driest (1.4").