Mason, IL
Full City Profile · Illinois · Clay County County
2.7
/5.0
C+
Fair
365
Population
283/sq mi density
$63,472
Median Income
$25,737 per capita
$89,300
Home Value
$198,468 Zillow
$588
Median Rent
41.7% income on rent
54°F
Avg Temperature
51
Violent Crime/100K
563 property/100K
C+
Overall
2.7 / 5.0
Fair overall score based on economy, affordability, safety and education
B
Economy
3.2 / 5.0
$63,472 median income, 4.6% unemployment
A+
Affordability
5.0 / 5.0
$89,300 home value, $588/mo rent
F
Safety
1.0 / 5.0
51 violent crimes/100K
F
Education
1.5 / 5.0
5.8% bachelor's degree or higher
Mason experiences four distinct seasons with an average annual temperature of 54°F (12°C). Winters average 29°F in January while summers reach 77°F in July. Annual precipitation totals 44.0 inches. The area receives 14.6 inches of snow annually.
Temperature
29°F Jan (-2°C)
77°F Jul (25°C)
| Annual Average | 54.4°F |
| 1% above US avg | |
| January Average | 29°F (-2°C) |
| July Average | 77°F (25°C) |
Geography
| Elevation | 587 ft (179 m) |
| Area | 1.3 sq mi (3.3 km²) |
| Population Density | 283/sq mi |
| Coordinates | 38.9543°N, 88.6271°W |
| Timezone | America/Chicago |
| County | Clay County County |
| Nearest Airport | Lawrenceville-Vincennes International (LWV) 57 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 41.1 / 100 |
| Social Vulnerability | 52.0 / 100 |
| Community Resilience | 88.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively 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)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 29°F (-2°C) | 2.9 in | Coldest |
| February | 33°F (1°C) | 2.4 in | Driest |
| March | 43°F (6°C) | 3.3 in | |
| April | 54°F (12°C) | 4.8 in | |
| May | 65°F (18°C) | 5.3 in | Wettest |
| June | 74°F (23°C) | 4.9 in | |
| July | 77°F (25°C) | 4.3 in | Warmest |
| August | 75°F (24°C) | 3.2 in | |
| September | 68°F (20°C) | 2.9 in | |
| October | 56°F (14°C) | 3.5 in | |
| November | 44°F (7°C) | 3.7 in | |
| December | 34°F (1°C) | 2.8 in |
Mason has a seasonal temperature swing of 48°F / from 29°F in January to 77°F in July. Total annual precipitation is 44.0 inches, with May being the wettest month (5.3") and February the driest (2.4").