South Jacksonville, IL
Full City Profile · Illinois · Morgan County County
3.0
/5.0
B
Good
3,255
Population
1,440/sq mi density
$53,438
Median Income
$34,632 per capita
$137,100
Home Value
$151,461 Zillow
$631
Median Rent
26.3% income on rent
53°F
Avg Temperature
220
Violent Crime/100K
439 property/100K
B
Overall
3.0 / 5.0
Good overall score based on economy, affordability, safety and education
C+
Economy
2.9 / 5.0
$53,438 median income, 9.9% unemployment
A+
Affordability
5.0 / 5.0
$137,100 home value, $631/mo rent
F
Safety
1.0 / 5.0
220 violent crimes/100K
C+
Education
2.9 / 5.0
24.3% bachelor's degree or higher
South 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. Annual precipitation totals 41.4 inches. The area receives 16.2 inches of snow annually.
Temperature
26°F Jan (-3°C)
76°F Jul (24°C)
| Annual Average | 52.8°F |
| 2% below US avg | |
| January Average | 26°F (-3°C) |
| July Average | 76°F (24°C) |
Geography
| Elevation | 623 ft (190 m) |
| Area | 2.3 sq mi (5.9 km²) |
| Population Density | 1,440/sq mi |
| Coordinates | 39.6994°N, 90.2240°W |
| Timezone | America/Chicago |
| County | Morgan County County |
| Nearest Airport | Quincy Regional-Baldwin Field (UIN) 54 miles away |
Precipitation & Snow
Air Quality
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)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 26°F (-3°C) | 2.2 in | Coldest |
| February | 31°F (-1°C) | 2.0 in | Driest |
| March | 41°F (5°C) | 3.0 in | |
| April | 53°F (12°C) | 4.5 in | |
| May | 64°F (18°C) | 5.1 in | Wettest |
| June | 73°F (23°C) | 5.0 in | |
| July | 76°F (24°C) | 4.0 in | Warmest |
| August | 75°F (24°C) | 3.3 in | |
| September | 67°F (20°C) | 3.8 in | |
| October | 55°F (13°C) | 3.1 in | |
| November | 42°F (6°C) | 3.1 in | |
| December | 31°F (-0°C) | 2.4 in |
South Jacksonville has a seasonal temperature swing of 50°F / from 26°F in January to 76°F in July. Total annual precipitation is 41.4 inches, with May being the wettest month (5.1") and February the driest (2.0").