National Weather ServiceMarylandFlash Flood WarningArchive to October 1, 2026
Flash Flood Warnings in Maryland
The National Weather Service issued 67 flash flood warnings for Maryland in 2025 and 47 a year on average in 2008-2025; in 2021-2025 it had the 32nd most of any state. 2026 through September: 43, 6% below the average of 46 for those months in 2008-2025. Baltimore was covered most often (233 times since 2008).
How many flash flood warnings does Maryland get?
Every flash flood warning that covered part of Maryland. 2026 is an outline: the year is not over.
The numbers
| Year | Count |
|---|---|
| 2026 (through September) | 43 |
| 2025 | 67 |
| 2024 | 45 |
| 2023 | 36 |
| 2022 | 42 |
| 2021 | 42 |
| 2020 | 60 |
| 2019 | 29 |
| 2018 | 63 |
| 2017 | 44 |
| 2016 | 25 |
| 2015 | 52 |
| 2014 | 41 |
| 2013 | 49 |
| 2012 | 50 |
| 2011 | 110 |
| 2010 | 34 |
| 2009 | 41 |
| 2008 | 13 |
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
When in the year does Maryland get them?
Sum of 2008-2025; the busiest month is labelled.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
Where in Maryland?
| County or forecast zone | Since 2008 | Since 2023 | Last issued |
|---|---|---|---|
| Baltimore | 233 | 53 | August 10, 2026 |
| Montgomery | 168 | 36 | August 7, 2026 |
| Prince Georges | 150 | 24 | July 28, 2026 |
| Baltimore City | 145 | 31 | August 10, 2026 |
| Harford | 103 | 22 | August 10, 2026 |
| Anne Arundel | 102 | 24 | July 28, 2026 |
| Howard | 101 | 17 | July 21, 2026 |
| Frederick | 75 | 9 | August 10, 2026 |
| Carroll | 66 | 6 | July 31, 2025 |
| Queen Anne's | 60 | 7 | August 20, 2026 |
| Cecil | 57 | 5 | July 31, 2025 |
| Caroline | 55 | 11 | August 20, 2026 |
The NWS issues these products for counties or forecast zones; a zone can be part of a county or a mountain range.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
The latest flash flood warnings for Maryland in AreaZine's record
NWS WakefieldWarningSeptember 13, 2026
Flash Flood Warning: Worcester, MD
Expired 7:45 a.m. EDT, September 13, 2026
NWS Baltimore MD/WashingtonWarningSeptember 12, 2026
Flash Flood Warning: Garrett, MD
Expired 7:45 p.m. EDT, September 12, 2026
NWS WakefieldWarningAugust 28, 2026
Flash Flood Warning: Somerset and Wicomico, MD
Expired 3:30 p.m. EDT, August 28, 2026
NWS WakefieldWarningAugust 20, 2026
Flash Flood Warning: Somerset, Wicomico and Worcester, MD
Expired 12:00 a.m. EDT, August 21, 2026
NWS Mount HollyWarningAugust 20, 2026
Flash Flood Warning: Kent, Caroline and Queen Anne's, DE and MD
Expired 11:00 p.m. EDT, August 20, 2026
NWS Baltimore MD/WashingtonWarningAugust 11, 2026
Flash Flood Warning: Garrett, MD
Expired 4:15 a.m. EDT, August 11, 2026
NWS Baltimore MD/WashingtonWarningAugust 10, 2026
Flash Flood Warning: Baltimore, Harford and Baltimore City, MD
Expired 8:45 p.m. EDT, August 10, 2026
NWS Baltimore MD/WashingtonWarningAugust 10, 2026
Flash Flood Warning: Frederick and Washington County, MD
Expired 6:15 p.m. EDT, August 10, 2026
This list is AreaZine's record of the NWS alert feed, kept since April 6, 2026; the counts above come from the complete IEM archive.
Source: National Weather Service alerts (api.weather.gov).
What is a flash flood warning?
A flash flood warning means flash flooding is happening or about to happen: water rising fast in streams, streets or dry washes, usually within six hours of heavy rain or a dam or levee failure. A warning means the hazard is happening, about to happen, or very likely: act now to protect people and property. The national record · Every warning type in Maryland.