St. Johns, IL
Full City Profile · Illinois · Perry County County
3.4
/5.0
B
Good
134
Population
184/sq mi density
$39,286
Median Income
$25,780 per capita
$80,000
Home Value
$112,669 Zillow
$760
Median Rent
32.5% income on rent
56°F
Avg Temperature
B
Overall
3.4 / 5.0
Good overall score based on economy, affordability, safety and education
B
Economy
3.2 / 5.0
$39,286 median income, 5.7% unemployment
A+
Affordability
5.0 / 5.0
$80,000 home value, $760/mo rent
C
Education
2.1 / 5.0
13.6% bachelor's degree or higher
St. Johns enjoys a temperate climate with an average annual temperature of 56°F (13°C). Winters average 32°F in January while summers reach 77°F in July. Annual precipitation totals 47.7 inches. The area receives 11.9 inches of snow annually.
Temperature
32°F Jan (0°C)
77°F Jul (25°C)
| Annual Average | 56.0°F |
| 4% above US avg | |
| January Average | 32°F (0°C) |
| July Average | 77°F (25°C) |
Geography
| Elevation | 460 ft (140 m) |
| Area | 0.3 sq mi (0.8 km²) |
| Population Density | 184/sq mi |
| Coordinates | 38.0349°N, 89.2386°W |
| Timezone | America/Chicago |
| County | Perry County County |
| Nearest Airport | Cape Girardeau Regional (CGI) 61 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 72.1 / 100 |
| Social Vulnerability | 64.1 / 100 |
| Community Resilience | 82.2 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Relatively Moderate |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Low |
| Ice Storm | Relatively Low |
| Drought | Relatively Low |
| Cold Wave | Relatively Moderate |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 32°F (0°C) | 3.2 in | Coldest |
| February | 37°F (3°C) | 2.9 in | Driest |
| March | 46°F (8°C) | 4.4 in | |
| April | 57°F (14°C) | 5.4 in | |
| May | 66°F (19°C) | 5.5 in | Wettest |
| June | 74°F (24°C) | 4.8 in | |
| July | 77°F (25°C) | 3.9 in | Warmest |
| August | 76°F (24°C) | 3.3 in | |
| September | 68°F (20°C) | 3.4 in | |
| October | 58°F (14°C) | 3.7 in | |
| November | 45°F (7°C) | 4.1 in | |
| December | 36°F (2°C) | 3.2 in |
St. Johns has a seasonal temperature swing of 45°F / from 32°F in January to 77°F in July. Total annual precipitation is 47.7 inches, with May being the wettest month (5.5") and February the driest (2.9").