Alert archive / New Jersey / Gloucester County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Gloucester County, New Jersey, 2014

20 severe thunderstorm warnings in 2014. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

Gloucester County and its neighbors

Each county as a circle sized by its count in 2014. Tap one for its archive.

Severe Thunderstorm Warnings
20
Busiest month
July11 severe thunderstorm warnings
Busiest day
July 3, 20145 severe thunderstorm warnings

Over time

By month

Warning verification

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

13 of 20 severe thunderstorm warnings covering Gloucester County in 2014 had a qualifying storm report inside them; 5 of 5 hail, wind and damage reports fell inside a warning, on average 18 minutes after it went out.

Gloucester County, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings201335%5100%18 min

Each office's whole area, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Philadelphia/Mount Holly: severe thunderstorm warnings1679146%26780%24 min

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.

The alerts

Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Apr 22, 7:21 PM EDTSevere Thunderstorm WarningPHI39 min
Apr 22, 7:52 PM EDTSevere Thunderstorm WarningPHI38 min
May 22, 4:13 PM EDTSevere Thunderstorm WarningPHI62 min
May 22, 4:22 PM EDTSevere Thunderstorm WarningPHI53 min
May 22, 4:48 PM EDTSevere Thunderstorm WarningPHI42 min
May 27, 5:52 PM EDTSevere Thunderstorm WarningPHI53 min
Jun 19, 1:41 AM EDTSevere Thunderstorm WarningPHI64 min
Jul 2, 7:48 PM EDTSevere Thunderstorm WarningPHI27 min
Jul 2, 8:08 PM EDTSevere Thunderstorm WarningPHI52 min
Jul 2, 8:53 PM EDTSevere Thunderstorm WarningPHI67 min
Jul 3, 1:00 AM EDTSevere Thunderstorm WarningPHI45 min
Jul 3, 1:19 AM EDTSevere Thunderstorm WarningPHI56 min
Jul 3, 6:46 PM EDTSevere Thunderstorm WarningPHI44 min
Jul 8, 8:21 PM EDTSevere Thunderstorm WarningPHI69 min
Jul 13, 10:48 PM EDTSevere Thunderstorm WarningPHI37 min
Jul 14, 7:29 PM EDTSevere Thunderstorm WarningPHI46 min
Jul 14, 7:53 PM EDTSevere Thunderstorm WarningPHI67 min
Jul 27, 11:32 PM EDTSevere Thunderstorm WarningPHI58 min
Aug 31, 6:26 PM EDTSevere Thunderstorm WarningPHI34 min
Sep 6, 4:52 PM EDTSevere Thunderstorm WarningPHI36 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20132015

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.