Johnstown, CO
Full City Profile · Colorado · Weld County County
3.6
/5.0
B+
Good
18,075
Population
1,160/sq mi density
$130,851
Median Income
$48,568 per capita
$493,500
Home Value
$499,377 Zillow
$1,767
Median Rent
25.0% income on rent
49°F
Avg Temperature
177
Violent Crime/100K
3,057 property/100K
B+
Overall
3.6 / 5.0
Good overall score based on economy, affordability, safety and education
A+
Economy
4.7 / 5.0
$130,851 median income, 4.2% unemployment
A+
Affordability
4.6 / 5.0
$493,500 home value, $1,767/mo rent
F
Safety
1.0 / 5.0
177 violent crimes/100K
B+
Education
4.0 / 5.0
37.0% bachelor's degree or higher
Johnstown experiences four distinct seasons with an average annual temperature of 49°F (9°C). Winters average 28°F in January while summers reach 72°F in July. Annual precipitation totals 14.4 inches. The area receives 47.0 inches of snow annually. Air quality is rated Moderate with a median AQI of 54.
Temperature
28°F Jan (-2°C)
72°F Jul (22°C)
| Annual Average | 48.7°F |
| 10% below US avg | |
| January Average | 28°F (-2°C) |
| July Average | 72°F (22°C) |
Geography
| Elevation | 4,840 ft (1,475 m) |
| Area | 13.6 sq mi (35.2 km²) |
| Population Density | 1,160/sq mi |
| Coordinates | 40.3072°N, 104.9112°W |
| Timezone | America/Denver |
| County | Weld County County |
| Nearest Airport | Northern Colorado Regional (FNL) 11 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 54.0 |
| Rating | Moderate |
| Good Days % | 40.7% |
| Unhealthy Days | 21 |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0491 ppm |
| NO₂ (Nitrogen Dioxide) | 11.5 ppb |
| CO (Carbon Monoxide) | 0.20 ppm |
| PM2.5 (Fine Particles) | 7.7 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 89.2 / 100 |
| Social Vulnerability | 11.4 / 100 |
| Community Resilience | 56.2 / 100 |
Hazard Breakdown
| Tornado | Relatively High |
| Earthquake | Relatively Low |
| Wildfire | Relatively Low |
| Flood | Relatively Moderate |
| Hail | Relatively High |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively High |
| Lightning | Relatively High |
| Ice Storm | Relatively Moderate |
| Drought | Relatively Low |
| Cold Wave | Relatively High |
| Landslide | Very Low |
| Volcano | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 28°F (-2°C) | 0.4 in | Coldest, Driest |
| February | 31°F (-1°C) | 0.4 in | |
| March | 40°F (4°C) | 0.9 in | |
| April | 47°F (8°C) | 1.7 in | |
| May | 55°F (13°C) | 2.6 in | Wettest |
| June | 66°F (19°C) | 1.8 in | |
| July | 72°F (22°C) | 1.5 in | Warmest |
| August | 70°F (21°C) | 1.4 in | |
| September | 62°F (16°C) | 1.4 in | |
| October | 49°F (9°C) | 1.1 in | |
| November | 37°F (3°C) | 0.7 in | |
| December | 29°F (-2°C) | 0.5 in |
Johnstown has a seasonal temperature swing of 44°F / from 28°F in January to 72°F in July. Total annual precipitation is 14.4 inches, with May being the wettest month (2.6") and January the driest (0.4").