Weather & Climate in Bryantown, MD
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Bryantown experiences four distinct seasons with an average annual temperature of 55°F (13°C). Winters average 35°F in January while summers reach 76°F in July. Annual precipitation totals 48.1 inches (wetter than the 38-inch national average). The area receives 15.1 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 41. 86% of days have good air quality. The city sits at an elevation of 104 feet.
Temperature
35°F Jan (1°C)
76°F Jul (24°C)
| Annual Average | 55.1°F |
| 2% above US avg | |
| January Average | 35°F (1°C) |
| July Average | 76°F (24°C) |
Geography
| Elevation | 104 ft (32 m) |
| Area | 4.1 sq mi (10.7 km²) |
| Population Density | 87/sq mi |
| Coordinates | 38.5488°N, 76.8422°W |
| Timezone | America/New_York |
| County | Calvert County County |
| Nearest Airport | St Mary's County Regional (LTW) 23 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 41.0 |
| Rating | Good |
| Good Days % | 85.7% |
| Unhealthy Days | 1 |
Natural Hazard Risk
| Overall Risk | Very Low |
| Risk Score | 28.9 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 93.8 / 100 |
Hazard Breakdown
| Tornado | Very Low |
| Hurricane | Relatively Moderate |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Very Low |
| Hail | Very Low |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Low |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Low |
| Drought | Relatively Moderate |
| Cold Wave | Relatively Low |
| Landslide | Relatively Low |
| Coastal Flood | Relatively Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
41 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M5.8.
| Aug 23, 2011 | 11 km SSW of Mineral, Virginia | M5.8 | 119 km | 6 km |
| Aug 25, 2011 | 8 km SW of Mineral, Virginia | M4.5 | 119 km | 7 km |
| Aug 24, 2011 | 11 km SSW of Mineral, Virginia | M4.2 | 120 km | 0 km |
| Mar 15, 1991 | 7 km NNW of Goochland, Virginia | M3.8 | 129 km | 16 km |
| Jul 16, 2010 | 5 km NNW of Barnesville, Maryland | M3.6 | 93 km | 7 km |
| May 5, 2003 | Virginia | M3.6 | 142 km | 13 km |
| Aug 24, 2011 | 16 km NNW of Goochland, Virginia | M3.4 | 126 km | 0 km |
| Sep 1, 2011 | 7 km SSW of Mineral, Virginia | M3.4 | 116 km | 3 km |
| Sep 22, 2001 | 5 km E of Pantops, Virginia | M3.2 | 148 km | 0 km |
| Jan 30, 2012 | 9 km SSE of Louisa, Virginia | M3.1 | 120 km | 3 km |
| Jan 17, 2016 | 3 km NE of Ranson, West Virginia | M3.0 | 121 km | 5 km |
| Oct 2, 2010 | 10 km NNW of Ashland, Virginia | M3.0 | 97 km | 19 km |
| Oct 12, 2011 | 9 km S of Louisa, Virginia | M3.0 | 120 km | 4 km |
| Mar 26, 2012 | 13 km S of Louisa, Virginia | M3.0 | 123 km | 9 km |
| Aug 3, 1995 | 13 km N of Williamsburg, Virginia | M2.9 | 129 km | 1 km |
| Aug 23, 2011 | 9 km SSW of Mineral, Virginia | M2.8 | 118 km | 0 km |
| Mar 15, 2015 | 6 km SW of Mineral, Virginia | M2.8 | 117 km | 5 km |
| Jan 14, 2025 | 1 km NNE of Wyndham, Virginia | M2.8 | 115 km | 0 km |
| Mar 15, 1993 | 5 km W of Columbia, Maryland | M2.7 | 76 km | 5 km |
| Feb 19, 2012 | 12 km S of Louisa, Virginia | M2.7 | 122 km | 3 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
7 hurricanes (Category 1+) recorded within 500 km since 1980. Strongest on record: Category 3.
| Year | Name | Category | Max Wind | Closest |
| 2014 | Arthur | Category 2 | 92 mph | 290 km |
| 2011 | Irene | Category 1 | 75 mph | 168 km |
| 2003 | Isabel | Category 1 | 75 mph | 219 km |
| 1999 | Floyd | Category 1 | - | 205 km |
| 1991 | Bob | Category 3 | 115 mph | 286 km |
| 1986 | Charley | Category 1 | 81 mph | 192 km |
| 1985 | Gloria | Category 2 | 98 mph | 205 km |
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tornado History
411 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 10 fatalities, 349 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Apr 28, 2002 | EF4 | 29 km | 38.0 mi | 3 |
| Sep 24, 2001 | EF4 | 99 km | 10.0 mi | 0 |
| Feb 24, 2016 | EF3 | 84 km | 30.3 mi | 0 |
| Sep 17, 2004 | EF3 | 83 km | 9.0 mi | 0 |
| Apr 28, 2002 | EF3 | 49 km | 18.0 mi | 0 |
| Sep 24, 2001 | EF3 | 44 km | 17.5 mi | 2 |
| Sep 5, 1979 | EF3 | 33 km | 17.9 mi | 1 |
| Jan 26, 1978 | EF3 | 40 km | 0.7 mi | 1 |
| Apr 1, 1973 | EF3 | 51 km | 9.8 mi | 0 |
| Nov 2, 1966 | EF3 | 65 km | 0.1 mi | 0 |
| Jun 9, 1961 | EF3 | 75 km | 0.1 mi | 0 |
| Sep 1, 2021 | EF2 | 40 km | 11.4 mi | 0 |
| May 3, 2021 | EF2 | 70 km | 4.4 mi | 0 |
| Aug 4, 2020 | EF2 | 95 km | 1.3 mi | 0 |
| Nov 2, 2018 | EF2 | 93 km | 5.5 mi | 0 |
| Jul 23, 2017 | EF2 | 63 km | 2.4 mi | 0 |
| May 8, 2008 | EF2 | 63 km | 3.4 mi | 0 |
| Sep 17, 2004 | EF2 | 81 km | 13.0 mi | 0 |
| Sep 17, 2004 | EF2 | 59 km | 15.0 mi | 0 |
| Sep 17, 2004 | EF2 | 82 km | 8.0 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Wildfire History
20 wildfires (100+ acres) recorded within 100 km. Largest: BESTPITCH (7,743 acres, 2017).
| Year | Name | Acres Burned | Distance |
| 2017 | BESTPITCH | 7,743 | 75 km |
| 2004 | RETAINING ECOLOGICAL HEALTH | 5,678 | 69 km |
| 2014 | BLACKWATER MARSH WUI BURNS FY14 | 5,433 | 71 km |
| 2005 | MARSH RX-FWS | 4,380 | 72 km |
| 2007 | GUINEA MARSH | 4,173 | 79 km |
| 2009 | DOCTORS CREEK | 3,686 | 78 km |
| 1999 | FB R O C I | 3,525 | 73 km |
| 2019 | MDBWR-FY19-RX-MDWHS SUPPORT | 3,197 | 72 km |
| 2011 | COMPARTMENT J | 2,775 | 71 km |
| 2005 | ISLAND CREEK | 2,729 | 79 km |
| 2004 | UNNAMED | 2,156 | 79 km |
| 1992 | UNNAMED | 2,038 | 76 km |
| 2005 | VEGETATION RESEARCH | 1,926 | 76 km |
| 2011 | THOROFARE | 1,850 | 76 km |
| 1987 | UNNAMED | 1,692 | 68 km |
| 2004 | ROBBINS FIRE | 1,612 | 72 km |
| 2004 | BLACKWATER HAZARD FUEL REDUCTION | 1,518 | 64 km |
| 2009 | BECKERS ISLAND | 1,398 | 73 km |
| 2022 | ELLIOTTS ISLAND | 1,324 | 80 km |
| 2006 | UNNAMED | 1,260 | 69 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 35°F (1°C) | 3.3 in | Coldest |
| February | 37°F (3°C) | 3.0 in | Driest |
| March | 44°F (7°C) | 4.2 in | |
| April | 55°F (13°C) | 3.3 in | |
| May | 63°F (17°C) | 4.3 in | |
| June | 71°F (22°C) | 4.2 in | |
| July | 76°F (24°C) | 4.6 in | Warmest |
| August | 74°F (23°C) | 4.8 in | |
| September | 67°F (20°C) | 4.9 in | Wettest |
| October | 56°F (13°C) | 4.2 in | |
| November | 46°F (8°C) | 3.3 in | |
| December | 38°F (4°C) | 4.0 in |
Bryantown has a seasonal temperature swing of 41°F / from 35°F in January to 76°F in July. Total annual precipitation is 48.1 inches, with September being the wettest month (4.9") and February the driest (3.0").