Flash Flood Warnings in New York, 2019

By month

45 of 65 flash flood warnings covering New York in 2019 had a flash flood report inside them; 95 of 110 flash flood reports fell inside a warning, on average 69 minutes after it went out.

New York, 2019

Each office's whole area, 2019

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.

• Richmond County6
• Cattaraugus County5
• Chenango County5
• Nassau County5
• Erie County4
• Chemung County4
• Ontario County4
• Orange County4
• Bronx County4
• New York County4
• Queens County4
• Westchester County4
• Herkimer County4
• Niagara County3
• Oneida County3
• Chautauqua County3
• Tioga County3
• Cortland County3
• Steuben County3
• Rockland County3
• Kings County3
• Suffolk County3
• Madison County3
• Onondaga County2
• Schuyler County2
• Livingston County2
• Monroe County2
• Wayne County2
• Essex County2
• Broome County2
• Dutchess County2
• Tompkins County2
• Otsego County2
• Hamilton County2
• Wyoming County1
• Oswego County1
• Warren County1
• Franklin County1
• Allegany County1
• Sullivan County1

1. November 1, 20198flash flood warnings
2. June 20, 20196flash flood warnings
3. July 18, 20194flash flood warnings
4. June 19, 20193flash flood warnings
5. July 5, 20193flash flood warnings
6. July 17, 20193flash flood warnings
7. July 22, 20193flash flood warnings
8. July 23, 20193flash flood warnings
9. August 17, 20193flash flood warnings
10. May 19, 20192flash flood warnings
11. June 1, 20192flash flood warnings
12. July 4, 20192flash flood warnings

Alerts in force nowTornadoes on recordThe radar archive20182020

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.