Flash Flood Warnings in Maryland, 2013

By month

36 of 49 flash flood warnings covering Maryland in 2013 had a flash flood report inside them; 43 of 54 flash flood reports fell inside a warning, on average 70 minutes after it went out.

Maryland, 2013

Each office's whole area, 2013

An office's figures cover every county it serves, including across state lines.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

• Prince George's County12
• Montgomery County11
• Howard County9
• Baltimore County9
• Anne Arundel County6
• Harford County6
• City of Baltimore6
• Carroll County5
• Charles County5
• Calvert County4
• Caroline County4
• Cecil County4
• Frederick County3
• Saint Mary's County3
• Talbot County3
• Kent County3
• Queen Anne's County3
• Dorchester County2
• Wicomico County1
• Worcester County1
• Allegany County1

1. July 12, 20137flash flood warnings
2. June 18, 20136flash flood warnings
3. June 10, 20135flash flood warnings
4. June 28, 20134flash flood warnings
5. June 11, 20133flash flood warnings
6. June 13, 20133flash flood warnings
7. July 21, 20133flash flood warnings
8. January 31, 20132flash flood warnings
9. May 23, 20132flash flood warnings
10. June 7, 20132flash flood warnings
11. June 30, 20132flash flood warnings
12. January 30, 20131flash flood warnings

Alerts in force nowTornadoes on recordThe radar archive20122014

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. Warning verification from the Mesonet's Cow. Rebuilt daily.