Rio, IL
Full City Profile · Illinois · Mercer County County
3.6
/5.0
B+
Good
210
Population
677/sq mi density
$62,917
Median Income
$29,852 per capita
$104,700
Home Value
$164,950 Zillow
$771
Median Rent
28.5% income on rent
50°F
Avg Temperature
B+
Overall
3.6 / 5.0
Good overall score based on economy, affordability, safety and education
B+
Economy
3.7 / 5.0
$62,917 median income, 3.0% unemployment
A+
Affordability
5.0 / 5.0
$104,700 home value, $771/mo rent
C
Education
2.1 / 5.0
13.8% bachelor's degree or higher
Rio experiences four distinct seasons with an average annual temperature of 50°F (10°C). Winters average 22°F in January while summers reach 75°F in July. Annual precipitation totals 37.4 inches. The area receives 26.8 inches of snow annually.
Temperature
22°F Jan (-6°C)
75°F Jul (24°C)
| Annual Average | 50.2°F |
| 7% below US avg | |
| January Average | 22°F (-6°C) |
| July Average | 75°F (24°C) |
Geography
| Elevation | 779 ft (237 m) |
| Area | 0.1 sq mi (0.3 km²) |
| Population Density | 677/sq mi |
| Coordinates | 41.1093°N, 90.3988°W |
| Timezone | America/Chicago |
| County | Mercer County County |
| Nearest Airport | Quad Cities International (MLI) 24 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 8.8 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 85.7 / 100 |
Hazard Breakdown
| Tornado | Very Low |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Very Low |
| Hail | Very Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Low |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 22°F (-6°C) | 1.7 in | Coldest, Driest |
| February | 26°F (-3°C) | 1.9 in | |
| March | 38°F (3°C) | 2.4 in | |
| April | 51°F (10°C) | 3.7 in | |
| May | 62°F (17°C) | 4.8 in | Wettest |
| June | 72°F (22°C) | 4.1 in | |
| July | 75°F (24°C) | 3.9 in | Warmest |
| August | 73°F (23°C) | 3.5 in | |
| September | 66°F (19°C) | 3.5 in | |
| October | 53°F (12°C) | 2.9 in | |
| November | 39°F (4°C) | 2.8 in | |
| December | 28°F (-2°C) | 2.2 in |
Rio has a seasonal temperature swing of 53°F / from 22°F in January to 75°F in July. Total annual precipitation is 37.4 inches, with May being the wettest month (4.8") and January the driest (1.7").