Flash Flood in Maryland
Every flash flood event the National Weather Service has filed in Maryland, year by year, with the most significant episodes. Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
The most significant on the map
The most significant flash flood episodes in Maryland.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The record
- Events
- 1,735
- Deaths
- 22
- Injuries
- 31
- Damage
- $166 million
Every year
The most significant
Ranked by deaths, injuries, damage and size together.
- Tornadoes and Flash Flooding in Maryland, September 24, 2001Severe thunderstorms moved through Central Maryland during the early evening of the 24th. One thunderstorm produced a devastating F3 tornado which was on the ground for 17.5 miles from College Park in Prince George's County to just east of Columbia in Howard County.
- Flash Flooding and Flood in Maryland, June 24 to 28, 2006A weak cold front settled over the forecast area from June 23 until June 27. Waves of low pressure rode northeast along the front. Flow in the atmosphere was parallel to the boundary, producing several rounds of training echoes.
- Flash Flood in Maryland, November 19, 2003Creeks and roads were flooded.
- Flash Flooding and Flooding in Maryland, July 30 to 31, 2016A boundary remained overhead on the 30th of July. Hot and humid conditions led to an unstable atmosphere. The instability along with the boundary caused a few severe thunderstorms to develop.
- Flash Flooding and Flooding in Maryland, June 27 to 28, 2015Potent low pressure passed by to our west, and the warm front associated with the low moved through our area during this time. Warm and moist air near and south of the boundary led to an unstable atmosphere, while forcing from the warm front provided the lift.
- Flash Flooding and Flooding in Maryland, September 1 to 3, 2021The remnants of Ida produced widespread flooding along with instances of flash flooding across the area. Tropical moisture infiltrated the area and there were moderate amounts of instability as well.
- Flash Flooding and Flooding in Maryland, May 27 to 28, 2018A cold front sagged into Maryland during the afternoon of May 27th. Heavy rain trained to the northeast of Baltimore early in the afternoon, causing flash flooding.
- Flash Flooding and Flooding in Maryland, August 31, 2018Showers and thunderstorms developed around a stalled boundary. A slow storm motion combined with copious amounts of moisture led to heavy rain.
- Tornadoes and Tropical Storm in Maryland, August 4 to 5, 2020Tropical Storm Isaias moved up the east coast, passing through southern Maryland on the morning of Tuesday, August 4th, 2020, spawning several tornadoes as well as flooding rain and tropical storm force winds.
- Flash Flood in Maryland, June 19, 1996
- Flash Flood and Flooding in Maryland, July 7 to 8, 2005The remnants of Tropical Storm Cindy moved across the Mid Atlantic on Thursday and Friday, July 7 and July 8. The primary hazardous conditions that developed were from the torrential rainfall associated with this storm.
- Tropical Storm and Flash Flooding in Maryland, August 27 to 28, 2011Hurricane Irene produced heavy flooding rain, tropical storm force wind gusts and caused one wind related death across the Eastern Shore. Preliminary damage estimates were around three million dollars and approximately 85,000 homes and businesses lost power.
- Tropical Storm and Storm Surge in Maryland, September 16, 1999Hurricane Floyd made landfall just east of Cape Fear, North Carolina in the early morning hours of the 16th and moved north-northeast across extreme southeast Virginia to near Ocean City, Maryland by evening on the 16th.
- Flash Flood in Maryland, June 19, 1996
- Flash Flooding and Hail in Maryland, July 14 to 15, 2000A cold front moved across the region during the evening of the 14th. Thunderstorms that developed ahead and along this front produced very heavy rainfall, frequent lightning, large hail, and winds in excess of 55 MPH. Across Baltimore County, heavy rain flooded several roads.
- Flash Flooding and Flooding in Maryland, September 7 to 8, 2011Abnormally moist atmosphere across the mid-Atlantic allowed showers and thunderstorms to produce exceptional rainfall rates across portions of Maryland as the remnants of Tropical Depression Lee interacted with a nearly stationary boundary near the Mason-Dixon line.
- Flash Flooding and High Wind in Maryland, September 16 to 18, 1999Hurricane Floyd battered the Maryland Eastern Shore on September 16th and brought with it torrential rains and damaging winds.
- Flash Flooding and Flooding in Maryland, May 15 to 17, 2018A cold front slowly sagged southward through Pennsylvania during the afternoon hours of May 15th. A line of storms spread ahead of this front, causing a widespread 1-3 inches of rain across North Central and Northeast Maryland.
- Flash Flooding in Maryland, July 31, 2025A slow moving cold front combined with a highly unstable atmosphere along with tropical moisture to produce slow moving thunderstorms with heavy rainfall. Some of these storms trained over the same areas, resulting in scattered to numerous instances of flash flooding.
- Flash Flooding and Flooding in Maryland, May 18 to 19, 2015A cold front was located to the north of the Mid-Atlantic and warm and humid conditions persisted through the evening hours. A bay breeze formed across North-Central Maryland and led to multiple rounds of showers and thunderstorms in this area.
- Flash Flooding in Maryland, January 30 to 31, 2013A upper level trough was moving eastward and across most of the eastern U.S. with a surface low pressure center across the eastern Great Lakes. A cold front moved through the Mid Atlantic with dew points in the low 60s ahead of frontal passage.
- Flash Flood and Damaging Winds in Maryland, June 28, 2005With a tropical airmass in place, strong to severe thunderstorms occurred. These thunderstorms produced damaging wind gusts and heavy rainfall across a large portion of the Mid-Appalachian and Mid-Atlantic regions.
- Flash Flooding and Flooding in Maryland, August 12 to 13, 2014High pressure resided across the east coast while a warm front was located across the Carolinas. Moist air continued to move into the Mid Atlantic as showers intensified ahead of the warm front. Heavy rain produced flooding in parts of the Washington DC and Baltimore Metro Areas.
- Tornado and Flash Flooding in Maryland, August 26, 1999A line of intense thunderstorms moved across much of Maryland during the afternoon, producing damaging winds and frequent lightning. Storm winds weakened and the speed of the line slowed as it moved south and east of Frederick and Carroll Counties.
- Tornadoes and Flash Flood in Maryland, June 16, 1998The approach of a cold front combined with impressive jet stream energy at upper-levels of the atmosphere acted on unstable air near the surface to produce a major severe weather episode across northern Maryland for the second time in three weeks.
More
Sources
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24.