Weather & Climate in Somerville, NJ

Temperature, precipitation, air quality, natural hazards, and monthly weather data.

Somerville experiences four distinct seasons with an average annual temperature of 51°F (11°C). Winters average 29°F in January while summers reach 74°F in July. The area gets 275 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 46.7 inches (wetter than the 38-inch national average). Air quality is rated Good with a median AQI of 39. The city sits at an elevation of 45 feet.

Temperature

29°F Jan (-2°C) 74°F Jul (23°C)

Annual Average	51.1°F
	5% below US avg
January Average	29°F (-2°C)
July Average	74°F (23°C)
Sunny Days	275 days/yr

Geography

Elevation	45 ft (14 m)
Area	2.4 sq mi (6.1 km²)
Population Density	5,538/sq mi
Coordinates	40.5697°N, 74.6077°W
Timezone	America/New_York
County	Somerset County County
Nearest Airport	Central Jersey Regional (JVI) 3 miles away

Precipitation & Snow

Annual Rainfall 46.7"

23% above US avg

Wettest Month (Jul) 5.04"

Driest Month (Feb) 3.03"

Air Quality

AQI Median	39.0
Rating	Good

Natural Hazard Risk

Overall Risk	Relatively Moderate
Risk Score	90.9 / 100
Social Vulnerability	10.6 / 100
Community Resilience	93.3 / 100

Hazard Breakdown

Tornado	Relatively Moderate
Hurricane	Relatively Moderate
Earthquake	Relatively Low
Wildfire	Very Low
Flood	Relatively High
Hail	Very Low
Strong Wind	Relatively High
Heat Wave	Relatively Moderate
Winter Weather	Relatively High
Lightning	Relatively High
Ice Storm	Relatively High
Drought	Relatively Low
Cold Wave	Relatively Moderate
Landslide	Very Low
Coastal Flood	Very Low

Source: FEMA National Risk Index v1.20 (Dec 2025)

Earthquake History

32 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M4.8.

Apr 5, 2024	2024 Tewksbury, New Jersey Earthquake	M4.8	19 km	3 km
Jan 16, 1994	2 km W of Sinking Spring, Pennsylvania	M4.6	124 km	5 km
Jan 16, 1994	0 km E of Sinking Spring, Pennsylvania	M4.2	121 km	5 km
Apr 5, 2024	7 km WSW of Gladstone, New Jersey	M3.7	18 km	4 km
Oct 23, 1990	3 km W of Hancocks Bridge, New Jersey	M3.2	140 km	10 km
Jan 9, 1992	4 km WNW of Robertsville, New Jersey	M3.1	32 km	8 km
Aug 26, 2003	4 km NNW of Milford, New Jersey	M3.1	42 km	3 km
Nov 14, 1997	0 km S of Rothsville, Pennsylvania	M3.0	147 km	5 km
Aug 3, 2025	0 km W of Little Ferry, New Jersey	M3.0	57 km	10 km
Oct 28, 1991	3 km WNW of Stamford, Connecticut	M3.0	103 km	10 km
Feb 3, 2009	1 km ESE of Victory Gardens, New Jersey	M3.0	34 km	0 km
Jan 16, 1994	0 km SSE of Sinking Spring, Pennsylvania	M2.9	122 km	5 km
Apr 27, 2024	7 km WSW of Gladstone, New Jersey	M2.9	18 km	5 km
May 24, 2024	6 km E of Califon, New Jersey	M2.9	20 km	7 km
May 10, 1993	1 km NW of Whitfield, Pennsylvania	M2.8	122 km	5 km
Aug 5, 2025	1 km N of Hillsdale, New Jersey	M2.8	69 km	12 km
Jul 1, 2009	3 km ESE of Pennsville, New Jersey	M2.8	127 km	5 km
Apr 12, 1991	2 km ENE of North Castle, New York	M2.7	103 km	9 km
Jan 25, 2015	4 km ESE of Downingtown, Pennsylvania	M2.6	109 km	2 km
Jul 5, 1996	2 km NW of Chester Heights, Pennsylvania	M2.6	105 km	18 km

Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.

Hurricane History

4 hurricanes (Category 1+) recorded within 500 km since 1980. Strongest on record: Category 2.

Year	Name	Category	Max Wind	Closest
2012	Sandy	Category 1	92 mph	280 km
2011	Irene	Category 1	75 mph	277 km
1991	Bob	Category 2	109 mph	206 km
1985	Gloria	Category 2	98 mph	106 km

Source: NOAA IBTrACS (Category 1+, 1980–2026).

Tornado History

282 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF3. Total: 16 fatalities, 214 injuries.

Date	Rating	Distance	Path	Fatalities
Jul 29, 2021	EF3	59 km	3.4 mi	0
May 31, 1998	EF3	91 km	20.0 mi	0
Jul 27, 1994	EF3	86 km	2.0 mi	3
Oct 18, 1990	EF3	17 km	0.5 mi	0
Jul 14, 1988	EF3	85 km	7.2 mi	0
Jul 26, 1981	EF3	85 km	3.3 mi	0
Sep 26, 1977	EF3	23 km	5.9 mi	0
Mar 21, 1976	EF3	66 km	0.5 mi	0
May 28, 1973	EF3	33 km	0.4 mi	0
May 28, 1973	EF3	27 km	0.4 mi	0
Jun 24, 1960	EF3	36 km	12.9 mi	0
Apr 1, 2023	EF2	54 km	1.6 mi	0
Apr 1, 2023	EF2	50 km	2.1 mi	0
Apr 1, 2023	EF2	69 km	0.1 mi	0
Feb 21, 2023	EF2	33 km	5.8 mi	0
Sep 1, 2021	EF2	74 km	8.3 mi	1
Jul 29, 2021	EF2	38 km	6.3 mi	0
Jul 29, 2021	EF2	97 km	4.2 mi	0
Aug 4, 2020	EF2	62 km	20.8 mi	0
Jul 29, 2009	EF2	67 km	4.6 mi	0

Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).

Tsunami History

3 tsunamis recorded within 500 km. Highest wave on record: 0.3 m (1 ft).

Year	Location	Cause	Max Wave	Deaths	Distance
1964	LONG ISLAND, NY	Meteorological	0.3 m	—	130 km
1895	HIGH BRIDGE, NJ	Earthquake	—	—	26 km
1840	PHILADELPHIA, PENNSYLVANIA	Earthquake	—	—	99 km

Source: NOAA/NCEI Historical Tsunami Database.

Wildfire History

20 wildfires (100+ acres) recorded within 100 km. Largest: UNNAMED (23,000 acres, 1985).

Year	Name	Acres Burned	Distance
1985	UNNAMED	23,000	81 km
1995	GREENWOOD STATE FOREST	21,271	86 km
2007	WARREN GROVE	15,315	100 km
2022	MULLICA RIVER FIRE	13,082	98 km
2019	SPRING HILL FIRE	8,182	88 km
2016	16 MILE	7,896	84 km
1992	FORKED RIVER MOUTAIN APR	5,093	84 km
2024	JENNINGS CREEK	5,069	73 km
1992	POWER PLANT	4,928	88 km
1992	UNNAMED	4,470	64 km
2024	TEA TIME HILL	4,444	87 km
2006	UNNAMED	3,780	95 km
2017	PENN SWAMP FIRE	3,587	99 km
2023	JIMMYS WATER HOLE	3,585	66 km
1989	SIMM PLACE	3,262	89 km
2002	UNNAMED	2,824	63 km
2007	ATSION	2,705	95 km
1992	FOUR MILE COLONY	2,647	79 km
1996	UNNAMED	2,625	100 km
2010	FORT DIX RANGE 1-14	2,615	62 km

Source: NIFC/IRWIN Wildfire Records (100+ acres).

Monthly Weather

Month	Avg Temperature	Precipitation	Summary
January	29°F (-2°C)	3.9 in	Coldest
February	31°F (-0°C)	3.0 in	Driest
March	40°F (4°C)	4.0 in
April	50°F (10°C)	4.1 in
May	60°F (16°C)	4.7 in
June	69°F (21°C)	4.1 in
July	74°F (23°C)	5.0 in	Warmest, Wettest
August	73°F (23°C)	4.5 in
September	65°F (19°C)	4.4 in
October	54°F (12°C)	3.7 in
November	44°F (7°C)	4.1 in
December	34°F (1°C)	3.8 in

Somerville has a seasonal temperature swing of 45°F / from 29°F in January to 74°F in July. Total annual precipitation is 49.3 inches, with July being the wettest month (5.0") and February the driest (3.0").

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