Alert archive / New Jersey / Burlington County

Flash Flood Warnings in Burlington County, New Jersey

233 flash flood warnings since 1986. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Burlington County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Flash Flood Warnings
233
Busiest year
202627 flash flood warnings
Average year
7over 34 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.

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

From 2008 to 2025, 88% of flash flood reports in Burlington County fell inside a flash flood warning issued on average 110 minutes before, and 35% of the flash flood warnings had no report inside them.

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20084325%1100%52 min
20094175%20%
20104175%1100%94 min
20118275%250%2 min
20126267%10%
201310910%367%35 min
20148450%2100%24 min
20156517%0
20169544%0
20176433%3100%131 min
201814750%4100%89 min
2019141029%1385%95 min
202011110%6100%90 min
2021171418%2692%181 min
20223233%0
20239811%5100%54 min
202414750%683%38 min
2025161131%8100%80 min

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

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.

The latest flash flood warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 3, 1:34 AM EDTFlash Flood WarningPHI4 hr
Aug 28, 1:48 PM EDTFlash Flood WarningPHI4 hr
Aug 27, 7:00 PM EDTFlash Flood WarningPHI3 hr
Aug 16, 11:38 PM EDTFlash Flood WarningPHI4 hr
Aug 7, 5:34 PM EDTFlash Flood WarningPHI3 hr
Aug 5, 1:23 PM EDTFlash Flood WarningPHI4 hr
Aug 5, 12:58 PM EDTFlash Flood WarningPHI6 hr
Aug 3, 10:44 AM EDTFlash Flood Warning Considerable damage threatPHI6 hr
Aug 3, 10:36 AM EDTFlash Flood WarningPHI6 hr
Aug 3, 9:08 AM EDTFlash Flood WarningPHI3 hr
Aug 3, 4:41 AM EDTFlash Flood WarningPHI2 hr
Jul 21, 4:38 PM EDTFlash Flood Warning Considerable damage threatPHI4 hr

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

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