Onslow, IA
Full City Profile · Iowa · Jones County County
3.3
/5.0
B
Good
306
Population
1,611/sq mi density
$42,813
Median Income
$20,722 per capita
$96,500
Home Value
$220,068 Zillow
48°F
Avg Temperature
B
Overall
3.3 / 5.0
Good overall score based on economy, affordability, safety and education
C+
Economy
2.9 / 5.0
$42,813 median income, 0.9% unemployment
A+
Affordability
5.0 / 5.0
$96,500 home value, /mo rent
C
Education
2.1 / 5.0
14.3% bachelor's degree or higher
Onslow experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 19°F in January while summers reach 73°F in July. Annual precipitation totals 39.5 inches. The area receives 31.1 inches of snow annually.
Temperature
19°F Jan (-7°C)
73°F Jul (23°C)
| Annual Average | 47.9°F |
| 11% below US avg | |
| January Average | 19°F (-7°C) |
| July Average | 73°F (23°C) |
Geography
| Elevation | 926 ft (282 m) |
| Area | 0.2 sq mi (0.6 km²) |
| Population Density | 1,611/sq mi |
| Coordinates | 42.1069°N, 91.0151°W |
| Timezone | America/Chicago |
| County | Jones County County |
| Nearest Airport | Monticello Regional (MXO) 11 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 32.7 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 78.9 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Very Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Very Low |
| Winter Weather | Relatively Low |
| Lightning | Very Low |
| Ice Storm | Relatively Low |
| 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 | 19°F (-7°C) | 1.3 in | Coldest, Driest |
| February | 23°F (-5°C) | 1.5 in | |
| March | 36°F (2°C) | 2.2 in | |
| April | 48°F (9°C) | 4.1 in | |
| May | 60°F (15°C) | 4.4 in | |
| June | 70°F (21°C) | 5.6 in | Wettest |
| July | 73°F (23°C) | 4.6 in | Warmest |
| August | 71°F (22°C) | 4.5 in | |
| September | 63°F (17°C) | 4.4 in | |
| October | 50°F (10°C) | 3.2 in | |
| November | 37°F (3°C) | 2.2 in | |
| December | 25°F (-4°C) | 1.7 in |
Onslow has a seasonal temperature swing of 53°F / from 19°F in January to 73°F in July. Total annual precipitation is 39.5 inches, with June being the wettest month (5.6") and January the driest (1.3").