Alert archive / Delaware / New Castle County / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in New Castle County, Delaware, 2019

57 severe thunderstorm warnings in 2019. An alert counts here when it covered this county. The archive of severe thunderstorm warnings reaches back to 1986.

New Castle County and its neighbors

Each county as a circle sized by its count in 2019. Tap one for its archive.

Severe Thunderstorm Warnings
57
Busiest month
July19 severe thunderstorm warnings
Busiest day
July 22, 20197 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.

42 of 57 severe thunderstorm warnings covering New Castle County in 2019 had a qualifying storm report inside them; 32 of 41 hail, wind and damage reports fell inside a warning, on average 23 minutes after it went out.

New Castle County, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings574226%4178%23 min

Each office's whole area, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Philadelphia/Mount Holly: severe thunderstorm warnings41027633%1,17587%25 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 15, 2:46 AM EDTSevere Thunderstorm WarningPHI44 min
Apr 15, 3:07 AM EDTSevere Thunderstorm WarningPHI38 min
Apr 26, 4:28 PM EDTSevere Thunderstorm WarningPHI47 min
Apr 26, 5:07 PM EDTSevere Thunderstorm WarningPHI38 min
May 23, 11:22 PM EDTSevere Thunderstorm WarningPHI38 min
May 28, 5:14 PM EDTSevere Thunderstorm WarningPHI46 min
May 28, 6:11 PM EDTSevere Thunderstorm WarningPHI64 min
May 28, 6:24 PM EDTSevere Thunderstorm WarningPHI48 min
May 28, 6:52 PM EDTSevere Thunderstorm WarningPHI38 min
May 28, 7:20 PM EDTSevere Thunderstorm WarningPHI40 min
May 29, 5:49 PM EDTSevere Thunderstorm WarningPHI41 min
May 29, 6:11 PM EDTSevere Thunderstorm WarningPHI34 min
May 29, 6:22 PM EDTSevere Thunderstorm WarningPHI53 min
Jun 2, 2:40 PM EDTSevere Thunderstorm WarningPHI50 min
Jun 2, 3:18 PM EDTSevere Thunderstorm WarningPHI42 min
Jun 2, 5:46 PM EDTSevere Thunderstorm WarningPHI44 min
Jun 2, 6:43 PM EDTSevere Thunderstorm WarningPHI47 min
Jun 16, 5:39 PM EDTSevere Thunderstorm WarningPHI36 min
Jun 20, 2:33 PM EDTSevere Thunderstorm WarningPHI57 min
Jun 28, 6:00 PM EDTSevere Thunderstorm WarningPHI33 min
Jun 29, 2:47 PM EDTSevere Thunderstorm WarningPHI28 min
Jun 29, 3:13 PM EDTSevere Thunderstorm WarningPHI8 min
Jun 29, 3:24 PM EDTSevere Thunderstorm WarningPHI36 min
Jun 29, 3:59 PM EDTSevere Thunderstorm WarningPHI46 min
Jun 29, 4:38 PM EDTSevere Thunderstorm WarningPHI52 min
Jul 2, 7:27 PM EDTSevere Thunderstorm WarningPHI48 min
Jul 2, 8:10 PM EDTSevere Thunderstorm WarningPHI50 min
Jul 6, 5:04 PM EDTSevere Thunderstorm WarningPHI17 min
Jul 6, 9:17 PM EDTSevere Thunderstorm WarningPHI43 min
Jul 11, 1:44 PM EDTSevere Thunderstorm WarningPHI61 min
Jul 11, 5:44 PM EDTSevere Thunderstorm WarningPHI61 min
Jul 11, 6:14 PM EDTSevere Thunderstorm WarningPHI61 min
Jul 17, 6:35 PM EDTSevere Thunderstorm WarningPHI40 min
Jul 17, 6:44 PM EDTSevere Thunderstorm WarningPHI46 min
Jul 17, 7:15 PM EDTSevere Thunderstorm WarningPHI45 min
Jul 17, 7:44 PM EDTSevere Thunderstorm WarningPHI46 min
Jul 21, 9:30 PM EDTSevere Thunderstorm WarningPHI45 min
Jul 21, 9:44 PM EDTSevere Thunderstorm WarningPHI46 min
Jul 21, 10:13 PM EDTSevere Thunderstorm WarningPHI47 min
Jul 21, 10:54 PM EDTSevere Thunderstorm WarningPHI25 min
Jul 22, 3:47 PM EDTSevere Thunderstorm WarningPHI58 min
Jul 22, 4:16 PM EDTSevere Thunderstorm WarningPHI59 min
Jul 22, 5:14 PM EDTSevere Thunderstorm WarningPHI61 min
Jul 31, 2:46 PM EDTSevere Thunderstorm WarningPHI44 min
Aug 1, 4:06 PM EDTSevere Thunderstorm WarningPHI54 min
Aug 1, 4:41 PM EDTSevere Thunderstorm WarningPHI21 min
Aug 7, 4:27 PM EDTSevere Thunderstorm WarningPHI63 min
Aug 7, 4:57 PM EDTSevere Thunderstorm WarningPHI63 min
Aug 7, 5:16 PM EDTSevere Thunderstorm WarningPHI59 min
Aug 7, 5:33 PM EDTSevere Thunderstorm WarningPHI42 min
Aug 18, 3:00 PM EDTSevere Thunderstorm WarningPHI45 min
Aug 22, 8:54 PM EDTSevere Thunderstorm WarningPHI66 min
Aug 22, 10:11 PM EDTSevere Thunderstorm WarningPHI64 min
Sep 4, 7:24 PM EDTSevere Thunderstorm WarningPHI51 min
Sep 4, 8:13 PM EDTSevere Thunderstorm WarningPHI62 min
Oct 31, 11:15 PM EDTSevere Thunderstorm WarningPHI60 min
Oct 31, 11:28 PM EDTSevere Thunderstorm WarningPHI62 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20182020

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.