Flash Flood Warnings in Maryland
1,567 flash flood warnings since 1986. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of flash flood warnings reaches back to 1986.
Flash Flood Warnings by county
Each county as a circle sized by its count since 1986. Tap one for its archive.
- Flash Flood Warnings
- 1,567
- Busiest year
- 1996115 flash flood warnings
- Average year
- 40over 39 years on file
Over time
By year
Before October 2007 these were issued for whole counties, and a storm crossing three counties was often three warnings; since then one polygon follows the storm. The count changed with the practice, not only with the weather.
By month of the year
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Baltimore County303
- Montgomery County259
- Prince George's County194
- City of Baltimore189
- Frederick County160
- Harford County152
- Howard County146
- Anne Arundel County131
- Garrett County119
- Washington County119
- Carroll County116
- Cecil County104
- Allegany County102
- Queen Anne's County84
- Caroline County73
- Charles County68
- Kent County67
- Saint Mary's County66
- Calvert County55
- Talbot County55
- Worcester County46
- Wicomico County43
- Dorchester County30
- Somerset County30
The latest flash flood warnings
The most recent on file, newest first.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 13, 4:43 AM EDT | Flash Flood Warning | AKQ | Worcester | 3 hr |
| Sep 12, 4:51 PM EDT | Flash Flood Warning | LWX | Garrett | 3 hr |
| Aug 28, 12:28 PM EDT | Flash Flood Warning | AKQ | Somerset, Wicomico | 98 min |
| Aug 20, 8:56 PM EDT | Flash Flood Warning | AKQ | Somerset, Wicomico, Worcester | 115 min |
| Aug 20, 6:53 PM EDT | Flash Flood Warning | PHI | Caroline, Queen Anne's | 105 min |
| Aug 11, 1:21 AM EDT | Flash Flood Warning | LWX | Garrett | 4 hr |
| Aug 10, 5:40 PM EDT | Flash Flood Warning | LWX | Baltimore, Harford, City of Baltimore | 88 min |
| Aug 10, 3:12 PM EDT | Flash Flood Warning | LWX | Frederick, Washington | 3 hr |
| Aug 7, 6:23 PM EDT | Flash Flood Warning | LWX | Montgomery | 46 min |
| Aug 7, 5:22 PM EDT | Flash Flood Warning | LWX | Baltimore, City of Baltimore | 3 hr |
| Aug 7, 4:43 PM EDT | Flash Flood Warning | LWX | Baltimore, Harford | 3 hr |
| Aug 6, 6:28 PM EDT | Flash Flood Warning | LWX | Baltimore | 2 hr |
Nearby
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Rebuilt daily.