History of Flash flood warning in Timeline

A flash flood warning is issued by weather forecasting agencies when a flash flood is imminent or occurring. Flash floods are sudden and violent, typically caused by heavy rain or dam breaks. Contributing factors include rainfall intensity and duration, topography, soil conditions, and ground cover. The warning alerts the public to the danger and allows them to take necessary precautions.

August 27, 2017: Flash Flood Emergency for Catastrophic Life Threatening Flooding

On August 27, 2017, the NWS issued a "Flash Flood Emergency for Catastrophic Life Threatening Flooding" in southeast Texas, due to the torrential rain brought by Hurricane Harvey.

September 10, 2017: Flash Flood Emergency for Life-Threatening Storm Surge

On September 10, 2017, the NWS issued a Flash Flood Emergency for life-threatening storm surge because of Hurricane Irma in southwestern Florida at the eye landfall.

February 6, 2020: Flash Flood Emergency for Tazewell County, Virginia

On February 6, 2020, the NWS issued a Flash Flood Emergency for Tazewell County, Virginia, due to a major storm causing the Clinch River to crest at its highest level in 40 years.

May 20, 2020: Flash Flood Emergency for the Tittabawassee River

On May 20, 2020, the NWS issued a Flash Flood Emergency for the Tittabawassee River in Midland County, Michigan, because of multiple dam failures causing the river to overflow and reach its highest crest since 1986.

July 6, 2020: Flash Flood Emergency for Tacony Creek and Frankford Creek

On July 6, 2020, the NWS issued a Flash Flood Emergency for Tacony Creek and Frankford Creek, located along Montgomery County, North Philadelphia, and Philadelphia's Frankford neighborhood, respectively.

September 1, 2021: First Ever Flash Flood Emergency for New York City, Philadelphia, Fairfield and New Haven Counties in Connecticut, and most of Central New Jersey

On September 1, 2021, the NWS issued a first-ever Flash Flood Emergency for New York City, Philadelphia, Fairfield and New Haven Counties in Connecticut, and most of Central New Jersey, after the remnants of Hurricane Ida transitioned and intensified into a post-tropical cyclone causing torrential rains. Some areas reported up to 10 inches of rain in less than an hour.

July 28, 2022: Flash Flood Emergencies in eastern Kentucky for catastrophic and deadly flooding

On July 28, 2022, the NWS issued several Flash Flood Emergencies in eastern Kentucky for catastrophic and deadly flooding.

March 27, 2023: Flash Flood Emergency for a dam break on the Head's Creek Reservoir

On March 27, 2023, the NWS issued a Flash Flood Emergency for a dam break on the Head's Creek Reservoir in Spaulding County, Georgia. A statement was later posted on Twitter.

September 27, 2024: Flash Flood Emergency issued for Metro Atlanta

On September 27, 2024, a Flash Flood Emergency was issued for Metro Atlanta as Hurricane Helene brought catastrophic flooding to the area.

October 9, 2024: Flash Flood Emergency for several counties in the Tampa Bay and Big Bend areas of Florida

On October 9, 2024, a Flash Flood Emergency was issued for several counties in the Tampa Bay and Big Bend areas of Florida as Hurricane Milton posed life-threatening flooding to a large portion of the West Coast.

August 8, 2025: Fatalities Confirmed from Flash Flood Emergencies in central Texas

As of August 8, 2025, at least 135 people have been confirmed dead from the Flash Flood Emergencies that occurred in central Texas from July 4-7, 2025 due to a slow-moving mesoscale convective complex.