All Countries
Weather & Climate in Union Bridge, MD
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Union Bridge experiences four distinct seasons with an average annual temperature of 53°F (12°C). Winters average 31°F in January while summers reach 75°F in July. The area gets 293 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). The area receives 27.5 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 41. The city sits at an elevation of 390 feet.
Temperature
31°F Jan (-0°C)
75°F Jul (24°C)
| Annual Average | 53.0°F |
| 2% below US avg | |
| January Average | 31°F (-0°C) |
| July Average | 75°F (24°C) |
| Sunny Days | 293 days/yr |
Geography
| Elevation | 390 ft (119 m) |
| Area | 1.1 sq mi (2.7 km²) |
| Population Density | 825/sq mi |
| Coordinates | 39.5710°N, 77.1728°W |
| Timezone | America/New_York |
| County | Carroll County County |
| Nearest Airport | Gettysburg Regional (GTY) 19 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 41.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 59.5 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 81.5 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Relatively Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Relatively Low |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively High |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Low |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | Very Low |
| Avalanche | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
29 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M4.6.
| Jan 16, 1994 | 2 km W of Sinking Spring, Pennsylvania | M4.6 | 128 km | 5 km |
| Jan 16, 1994 | 0 km E of Sinking Spring, Pennsylvania | M4.2 | 130 km | 5 km |
| Jul 16, 2010 | 5 km NNW of Barnesville, Maryland | M3.6 | 40 km | 7 km |
| Jun 13, 2019 | 9 km N of Blain, Pennsylvania | M3.4 | 99 km | 27 km |
| Oct 23, 1990 | 3 km W of Hancocks Bridge, New Jersey | M3.2 | 143 km | 10 km |
| Jun 3, 2010 | 4 km ENE of Franklintown, Pennsylvania | M3.1 | 60 km | 2 km |
| Jan 17, 2016 | 3 km NE of Ranson, West Virginia | M3.0 | 63 km | 5 km |
| Nov 14, 1997 | 0 km S of Rothsville, Pennsylvania | M3.0 | 101 km | 5 km |
| Apr 24, 2009 | 1 km S of Franklintown, Pennsylvania | M2.9 | 56 km | 1 km |
| Jan 16, 1994 | 0 km SSE of Sinking Spring, Pennsylvania | M2.9 | 130 km | 5 km |
| Sep 15, 2019 | 5 km ESE of East Berlin, Pennsylvania | M2.8 | 45 km | 5 km |
| May 10, 1993 | 1 km NW of Whitfield, Pennsylvania | M2.8 | 131 km | 5 km |
| Jul 1, 2009 | 3 km ESE of Pennsville, New Jersey | M2.8 | 145 km | 5 km |
| Oct 25, 2009 | 4 km ENE of Franklintown, Pennsylvania | M2.8 | 61 km | 1 km |
| Mar 15, 1993 | 5 km W of Columbia, Maryland | M2.7 | 44 km | 5 km |
| Oct 28, 1994 | 1 km E of Mount Vernon, Maryland | M2.7 | 58 km | — |
| Mar 11, 1995 | 0 km ENE of Landisville, Pennsylvania | M2.7 | 88 km | 5 km |
| Jan 25, 2015 | 4 km ESE of Downingtown, Pennsylvania | M2.6 | 138 km | 2 km |
| Jan 13, 1990 | 6 km ENE of Eldersburg, Maryland | M2.6 | 30 km | 5 km |
| Jun 25, 2021 | 2 km SE of Woodlawn, Maryland | M2.6 | 50 km | 3 km |
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Hurricane History
3 hurricanes (Category 1+) recorded within 500 km since 1980. Strongest on record: Category 2.
| Year | Name | Category | Max Wind | Closest |
| 2011 | Irene | Category 1 | 75 mph | 249 km |
| 1986 | Charley | Category 1 | 75 mph | 296 km |
| 1985 | Gloria | Category 2 | 98 mph | 265 km |
Source: NOAA IBTrACS (Category 1+, 1980–2026).
Tornado History
457 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF3. Total: 6 fatalities, 295 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Jul 14, 2004 | EF3 | 94 km | 7.5 mi | 0 |
| Sep 24, 2001 | EF3 | 73 km | 17.5 mi | 2 |
| Jul 19, 1996 | EF3 | 18 km | 2.2 mi | 0 |
| May 22, 1983 | EF3 | 16 km | 2.0 mi | 0 |
| Jun 7, 1980 | EF3 | 42 km | 1.5 mi | 0 |
| Sep 5, 1979 | EF3 | 88 km | 17.9 mi | 1 |
| Apr 1, 1973 | EF3 | 87 km | 9.8 mi | 0 |
| Jun 9, 1961 | EF3 | 63 km | 0.1 mi | 0 |
| Apr 16, 1961 | EF3 | 61 km | 0.1 mi | 0 |
| Apr 5, 1952 | EF3 | 30 km | 17.5 mi | 0 |
| Sep 1, 2021 | EF2 | 94 km | 11.4 mi | 0 |
| Apr 19, 2019 | EF2 | 69 km | 2.9 mi | 0 |
| Nov 2, 2018 | EF2 | 25 km | 5.5 mi | 0 |
| Jul 23, 2017 | EF2 | 98 km | 2.4 mi | 0 |
| Apr 28, 2011 | EF2 | 63 km | 2.6 mi | 0 |
| Sep 18, 2004 | EF2 | 70 km | 2.0 mi | 0 |
| Sep 17, 2004 | EF2 | 77 km | 2.0 mi | 0 |
| Sep 17, 2004 | EF2 | 38 km | 3.0 mi | 0 |
| Sep 17, 2004 | EF2 | 97 km | 5.0 mi | 0 |
| Sep 17, 2004 | EF2 | 85 km | 15.0 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 31°F (-0°C) | 2.9 in | Coldest |
| February | 33°F (0°C) | 2.7 in | Driest |
| March | 42°F (5°C) | 3.4 in | |
| April | 52°F (11°C) | 3.3 in | |
| May | 62°F (17°C) | 3.9 in | Wettest |
| June | 70°F (21°C) | 3.9 in | |
| July | 75°F (24°C) | 3.5 in | Warmest |
| August | 74°F (23°C) | 3.7 in | |
| September | 67°F (19°C) | 3.6 in | |
| October | 55°F (13°C) | 3.0 in | |
| November | 45°F (7°C) | 3.4 in | |
| December | 35°F (2°C) | 3.1 in |
Union Bridge has a seasonal temperature swing of 44°F / from 31°F in January to 75°F in July. Total annual precipitation is 40.3 inches, with May being the wettest month (3.9") and February the driest (2.7").