New Castle, DE
Full City Profile · Delaware · New Castle County County
3.6
/5.0
B+
Good
5,519
Population
1,586/sq mi density
$92,565
Median Income
$51,328 per capita
$262,100
Home Value
$281,557 Zillow
$1,675
Median Rent
21.6% income on rent
56°F
Avg Temperature
396
Violent Crime/100K
3,584 property/100K
B+
Overall
3.6 / 5.0
Good overall score based on economy, affordability, safety and education
A+
Economy
4.9 / 5.0
$92,565 median income, 1.1% unemployment
A+
Affordability
5.0 / 5.0
$262,100 home value, $1,675/mo rent
F
Safety
1.0 / 5.0
396 violent crimes/100K (4% above avg)
B+
Education
3.6 / 5.0
32.2% bachelor's degree or higher
New Castle enjoys a temperate climate with an average annual temperature of 56°F (13°C). Winters average 34°F in January while summers reach 78°F in July. Annual precipitation totals 45.3 inches. The area receives 20.2 inches of snow annually. Air quality is rated Good with a median AQI of 43.
Temperature
34°F Jan (1°C)
78°F Jul (25°C)
| Annual Average | 55.5°F |
| 3% above US avg | |
| January Average | 34°F (1°C) |
| July Average | 78°F (25°C) |
Geography
| Elevation | 5 ft (2 m) |
| Area | 3.5 sq mi (9.0 km²) |
| Population Density | 1,586/sq mi |
| Coordinates | 39.6700°N, 75.5665°W |
| Timezone | America/New_York |
| County | New Castle County County |
| Nearest Airport | Philadelphia International (PHL) 22 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
| Good Days % | 67.2% |
| Unhealthy Days | 4 |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0452 ppm |
| NO₂ (Nitrogen Dioxide) | 13.7 ppb |
| SO₂ (Sulfur Dioxide) | 0.34 ppb |
| PM2.5 (Fine Particles) | 8.9 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively High |
| Risk Score | 95.3 / 100 |
| Social Vulnerability | 28.5 / 100 |
| Community Resilience | 83.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Relatively Moderate |
| Earthquake | Relatively Moderate |
| Wildfire | Very Low |
| Flood | Relatively High |
| Hail | Very Low |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Moderate |
| Winter Weather | Very High |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively High |
| Drought | Relatively Moderate |
| Cold Wave | Relatively High |
| Landslide | Relatively Low |
| Coastal Flood | Relatively High |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tsunami History
2 tsunamis recorded within 500 km.
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1895 | HIGH BRIDGE, NJ | Earthquake | - | - | 125 km |
| 1840 | PHILADELPHIA, PENNSYLVANIA | Earthquake | - | - | 35 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 34°F (1°C) | 3.2 in | Coldest |
| February | 36°F (2°C) | 2.8 in | Driest |
| March | 43°F (6°C) | 4.2 in | |
| April | 54°F (12°C) | 3.5 in | |
| May | 64°F (18°C) | 3.6 in | |
| June | 73°F (23°C) | 4.7 in | Wettest |
| July | 78°F (25°C) | 4.4 in | Warmest |
| August | 76°F (24°C) | 4.0 in | |
| September | 69°F (21°C) | 4.4 in | |
| October | 57°F (14°C) | 3.7 in | |
| November | 47°F (8°C) | 3.1 in | |
| December | 38°F (3°C) | 3.9 in |
New Castle has a seasonal temperature swing of 44°F / from 34°F in January to 78°F in July. Total annual precipitation is 45.3 inches, with June being the wettest month (4.7") and February the driest (2.8").