Weather & Climate in Mountain Lake, NJ
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Mountain Lake experiences four distinct seasons with an average annual temperature of 50°F (10°C). Winters average 27°F in January while summers reach 72°F in July. Annual precipitation totals 48.2 inches (wetter than the 38-inch national average). The area receives 23.3 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 41. 73% of days have good air quality. The city sits at an elevation of 410 feet.
Temperature
27°F Jan (-3°C)
72°F Jul (22°C)
| Annual Average | 50.1°F |
| 7% below US avg | |
| January Average | 27°F (-3°C) |
| July Average | 72°F (22°C) |
Geography
| Elevation | 410 ft (125 m) |
| Area | 1.3 sq mi (3.4 km²) |
| Population Density | 501/sq mi |
| Coordinates | 40.8598°N, 74.9876°W |
| Timezone | America/New_York |
| County | Hunterdon County County |
| Nearest Airport | Lehigh Valley International (ABE) 28 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 41.0 |
| Rating | Good |
| Good Days % | 72.9% |
| Unhealthy Days | 0 |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 78.7 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 95.1 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Relatively Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Very Low |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively High |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | 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 | 26 km | 3 km |
| Jan 16, 1994 | 2 km W of Sinking Spring, Pennsylvania | M4.6 | 106 km | 5 km |
| Jan 16, 1994 | 0 km E of Sinking Spring, Pennsylvania | M4.2 | 105 km | 5 km |
| Apr 5, 2024 | 7 km WSW of Gladstone, New Jersey | M3.7 | 28 km | 4 km |
| Jan 9, 1992 | 4 km WNW of Robertsville, New Jersey | M3.1 | 78 km | 8 km |
| Aug 26, 2003 | 4 km NNW of Milford, New Jersey | M3.1 | 30 km | 3 km |
| Nov 14, 1997 | 0 km S of Rothsville, Pennsylvania | M3.0 | 133 km | 5 km |
| Oct 28, 1991 | 3 km WNW of Stamford, Connecticut | M3.0 | 121 km | 10 km |
| Aug 3, 2025 | 0 km W of Little Ferry, New Jersey | M3.0 | 79 km | 10 km |
| Feb 3, 2009 | 1 km ESE of Victory Gardens, New Jersey | M3.0 | 39 km | 0 km |
| Apr 27, 2024 | 7 km WSW of Gladstone, New Jersey | M2.9 | 27 km | 5 km |
| May 24, 2024 | 6 km E of Califon, New Jersey | M2.9 | 25 km | 7 km |
| Jan 16, 1994 | 0 km SSE of Sinking Spring, Pennsylvania | M2.9 | 105 km | 5 km |
| Aug 5, 2025 | 1 km N of Hillsdale, New Jersey | M2.8 | 82 km | 12 km |
| May 10, 1993 | 1 km NW of Whitfield, Pennsylvania | M2.8 | 104 km | 5 km |
| Jul 1, 2009 | 3 km ESE of Pennsville, New Jersey | M2.8 | 142 km | 5 km |
| Apr 12, 1991 | 2 km ENE of North Castle, New York | M2.7 | 117 km | 9 km |
| Mar 11, 1995 | 0 km ENE of Landisville, Pennsylvania | M2.7 | 146 km | 5 km |
| Jan 25, 2015 | 4 km ESE of Downingtown, Pennsylvania | M2.6 | 111 km | 2 km |
| Jul 5, 1996 | 2 km NW of Chester Heights, Pennsylvania | M2.6 | 114 km | 18 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
2 hurricanes (Category 1+) recorded within 500 km since 1980. Strongest on record: Category 2.
| Year | Name | Category | Max Wind | Closest |
| 1991 | Bob | Category 2 | 109 mph | 244 km |
| 1985 | Gloria | Category 2 | 98 mph | 145 km |
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tornado History
289 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF3. Total: 15 fatalities, 191 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Jul 29, 2021 | EF3 | 81 km | 3.4 mi | 0 |
| May 31, 1998 | EF3 | 50 km | 20.0 mi | 0 |
| May 31, 1998 | EF3 | 88 km | 8.3 mi | 0 |
| Jul 27, 1994 | EF3 | 83 km | 2.0 mi | 3 |
| Oct 18, 1990 | EF3 | 46 km | 0.5 mi | 0 |
| Jul 14, 1988 | EF3 | 65 km | 7.2 mi | 0 |
| Jul 26, 1981 | EF3 | 51 km | 3.3 mi | 0 |
| Sep 26, 1977 | EF3 | 67 km | 5.9 mi | 0 |
| Mar 21, 1976 | EF3 | 21 km | 0.5 mi | 0 |
| May 28, 1973 | EF3 | 42 km | 0.4 mi | 0 |
| May 28, 1973 | EF3 | 23 km | 0.4 mi | 0 |
| Jun 24, 1960 | EF3 | 68 km | 12.9 mi | 0 |
| Apr 1, 2023 | EF2 | 99 km | 1.6 mi | 0 |
| Apr 1, 2023 | EF2 | 93 km | 2.1 mi | 0 |
| Feb 21, 2023 | EF2 | 69 km | 5.8 mi | 0 |
| Sep 1, 2021 | EF2 | 86 km | 8.3 mi | 1 |
| Jul 29, 2021 | EF2 | 57 km | 6.3 mi | 0 |
| Aug 4, 2020 | EF2 | 87 km | 20.8 mi | 0 |
| Jun 13, 2018 | EF2 | 84 km | 2.9 mi | 0 |
| Feb 25, 2017 | EF2 | 78 km | 12.5 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
2 tsunamis recorded within 500 km.
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1895 | HIGH BRIDGE, NJ | Earthquake | - | - | 23 km |
| 1840 | PHILADELPHIA, PENNSYLVANIA | Earthquake | - | - | 119 km |
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
15 wildfires (100+ acres) recorded within 100 km. Largest: UNNAMED (23,000 acres, 1985).
| Year | Name | Acres Burned | Distance |
| 1985 | UNNAMED | 23,000 | 82 km |
| 2016 | 16 MILE | 7,896 | 40 km |
| 2024 | JENNINGS CREEK | 5,069 | 68 km |
| 2015 | ROOSA GAP | 2,747 | 99 km |
| 2009 | PENOBSCOT | 2,091 | 82 km |
| 2004 | CRYSTAL LAKE | 1,838 | 79 km |
| 1988 | UNNAMED | 833 | 84 km |
| 2012 | HOPEWELL FIRE | 812 | 96 km |
| 2020 | SEVEN PINES | 790 | 44 km |
| 1985 | UNNAMED | 737 | 74 km |
| 2015 | RAZOR FIRE | 728 | 59 km |
| 2015 | PIPELINE 1 | 666 | 65 km |
| 2016 | BEAR TOWN | 649 | 41 km |
| 2016 | SHERWOOD | 642 | 83 km |
| 1999 | WORTHINGTO | 514 | 18 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 27°F (-3°C) | 3.2 in | Coldest |
| February | 29°F (-2°C) | 2.7 in | Driest |
| March | 37°F (3°C) | 3.6 in | |
| April | 48°F (9°C) | 4.0 in | |
| May | 59°F (15°C) | 4.1 in | |
| June | 67°F (20°C) | 4.5 in | |
| July | 72°F (22°C) | 4.8 in | Warmest, Wettest |
| August | 71°F (22°C) | 4.6 in | |
| September | 64°F (18°C) | 4.6 in | |
| October | 52°F (11°C) | 4.8 in | |
| November | 41°F (5°C) | 3.3 in | |
| December | 33°F (0°C) | 4.1 in |
Mountain Lake has a seasonal temperature swing of 45°F / from 27°F in January to 72°F in July. Total annual precipitation is 48.2 inches, with July being the wettest month (4.8") and February the driest (2.7").