Gilson, IL
Full City Profile · Illinois · Knox County County
3.2
/5.0
B
Good
149
Population
452/sq mi density
$66,719
Median Income
$28,260 per capita
50°F
Avg Temperature
B
Overall
3.2 / 5.0
Good overall score based on economy, affordability, safety and education
A
Economy
4.3 / 5.0
$66,719 median income, 0.0% unemployment
C
Education
2.0 / 5.0
12.9% bachelor's degree or higher
Gilson experiences four distinct seasons with an average annual temperature of 50°F (10°C). Winters average 23°F in January while summers reach 74°F in July. Annual precipitation totals 40.5 inches. The area receives 25.4 inches of snow annually.
Temperature
23°F Jan (-5°C)
74°F Jul (23°C)
| Annual Average | 50.4°F |
| 7% below US avg | |
| January Average | 23°F (-5°C) |
| July Average | 74°F (23°C) |
Geography
| Elevation | 681 ft (208 m) |
| Area | 0.2 sq mi (0.6 km²) |
| Population Density | 452/sq mi |
| Coordinates | 40.8627°N, 90.1991°W |
| Timezone | America/Chicago |
| County | Knox County County |
| Nearest Airport | General Downing - Peoria International (PIA) 30 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 57.2 / 100 |
| Social Vulnerability | 49.8 / 100 |
| Community Resilience | 66.0 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Moderate |
| Winter Weather | Relatively Low |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Moderate |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 23°F (-5°C) | 2.1 in | Coldest, Driest |
| February | 27°F (-3°C) | 2.1 in | |
| March | 39°F (4°C) | 2.6 in | |
| April | 51°F (10°C) | 4.0 in | |
| May | 61°F (16°C) | 5.5 in | Wettest |
| June | 71°F (22°C) | 4.6 in | |
| July | 74°F (23°C) | 4.2 in | Warmest |
| August | 72°F (22°C) | 3.5 in | |
| September | 65°F (19°C) | 4.2 in | |
| October | 53°F (12°C) | 3.0 in | |
| November | 40°F (4°C) | 2.5 in | |
| December | 29°F (-2°C) | 2.2 in |
Gilson has a seasonal temperature swing of 51°F / from 23°F in January to 74°F in July. Total annual precipitation is 40.5 inches, with May being the wettest month (5.5") and January the driest (2.1").