Alton, IA
Full City Profile · Iowa · Plymouth County County
4.2
/5.0
A
Great
1,350
Population
707/sq mi density
$86,136
Median Income
$46,986 per capita
$204,600
Home Value
$314,966 Zillow
$750
Median Rent
18.8% income on rent
48°F
Avg Temperature
A
Overall
4.2 / 5.0
Strong
A+
Economy
4.7 / 5.0
$86,136 median income, 2.2% unemployment
A+
Affordability
5.0 / 5.0
$204,600 home value, $750/mo rent
C+
Education
2.8 / 5.0
21.9% bachelor's degree or higher
Alton experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 18°F in January while summers reach 73°F in July. Annual precipitation totals 28.3 inches. The area receives 26.6 inches of snow annually.
Temperature
18°F Jan (-8°C)
73°F Jul (23°C)
| Annual Average | 48.0°F |
| 11% below US avg | |
| January Average | 18°F (-8°C) |
| July Average | 73°F (23°C) |
Geography
| Elevation | 1,314 ft (401 m) |
| Area | 1.9 sq mi (4.8 km²) |
| Population Density | 707/sq mi |
| Coordinates | 42.9877°N, 96.0094°W |
| Timezone | America/Chicago |
| County | Plymouth County County |
| Nearest Airport | Sioux Gateway/Brig General Bud Day Field (SUX) 45 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 49.2 / 100 |
| Social Vulnerability | 26.2 / 100 |
| Community Resilience | 89.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Earthquake | Very Low |
| Wildfire | Relatively Low |
| Flood | Relatively Low |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Low |
| 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 | 18°F (-8°C) | 0.8 in | Coldest |
| February | 23°F (-5°C) | 0.7 in | Driest |
| March | 36°F (2°C) | 1.8 in | |
| April | 49°F (9°C) | 2.9 in | |
| May | 61°F (16°C) | 3.8 in | |
| June | 71°F (22°C) | 3.9 in | Wettest |
| July | 73°F (23°C) | 3.5 in | Warmest |
| August | 71°F (22°C) | 3.5 in | |
| September | 64°F (18°C) | 2.9 in | |
| October | 51°F (11°C) | 2.3 in | |
| November | 36°F (2°C) | 1.3 in | |
| December | 23°F (-5°C) | 1.0 in |
Alton has a seasonal temperature swing of 55°F / from 18°F in January to 73°F in July. Total annual precipitation is 28.3 inches, with June being the wettest month (3.9") and February the driest (0.7").