Flash Flood Warnings in New York, 2023

By month

97 of 156 flash flood warnings covering New York in 2023 had a flash flood report inside them; 262 of 306 flash flood reports fell inside a warning, on average 157 minutes after it went out.

New York, 2023

Each office's whole area, 2023

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.

• Westchester County18
• Essex County16
• Orange County15
• Putnam County13
• Rockland County12
• Sullivan County12
• Clinton County10
• New York County9
• Otsego County8
• Tioga County8
• Delaware County7
• Franklin County7
• Ulster County7
• Dutchess County7
• Bronx County7
• Queens County7
• Broome County7
• Chenango County7
• Monroe County6
• Suffolk County6
• Kings County5
• Nassau County5
• Washington County4
• Onondaga County4
• Oneida County4
• Madison County4
• Saratoga County3
• Steuben County3
• Lewis County3
• Albany County3
• Chemung County3
• Cortland County3
• Ontario County2
• Richmond County2
• Fulton County2
• Schoharie County2
• Hamilton County2
• Rensselaer County2
• Oswego County2
• Columbia County2

1. December 18, 202321flash flood warnings
2. July 9, 202319flash flood warnings
3. September 29, 202310flash flood warnings
4. July 14, 20239flash flood warnings
5. July 16, 20238flash flood warnings
6. July 7, 20237flash flood warnings
7. August 4, 20237flash flood warnings
8. September 11, 20237flash flood warnings
9. July 10, 20236flash flood warnings
10. July 2, 20235flash flood warnings
11. September 8, 20235flash flood warnings
12. July 18, 20234flash flood warnings

Alerts in force nowTornadoes on recordThe radar archive20222024

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.