Alert archive / New Jersey / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in New Jersey, 2009
142 severe thunderstorm warnings in 2009. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of severe thunderstorm warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Severe Thunderstorm Warnings
- 142
- Busiest month
- July47 severe thunderstorm warnings
- Busiest day
- June 26, 200913 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.
78 of 142 severe thunderstorm warnings covering New Jersey in 2009 had a qualifying storm report inside them; 130 of 160 hail, wind and damage reports fell inside a warning, on average 26 minutes after it went out.
New Jersey, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 142 | 78 | 45% | 160 | 81% | 26 min |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS New York, NY: severe thunderstorm warnings | 119 | 61 | 49% | 154 | 85% | 25 min |
| NWS Philadelphia/Mount Holly: severe thunderstorm warnings | 235 | 113 | 52% | 260 | 82% | 26 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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 29, 6:11 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Salem | 64 min |
| Mar 29, 7:09 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Hunterdon, Mercer, Middlesex, Monmouth, Ocean and 1 more | 51 min |
| Mar 29, 7:49 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 56 min |
| Mar 29, 7:53 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Middlesex, Monmouth, Ocean | 67 min |
| Mar 29, 8:19 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland, Ocean | 41 min |
| Apr 6, 6:59 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Camden, Cumberland, Gloucester, Salem | 61 min |
| Apr 6, 7:37 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 53 min |
| Apr 6, 10:27 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester | 48 min |
| May 7, 1:43 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Middlesex, Somerset | 62 min |
| May 7, 2:05 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Camden, Cumberland, Gloucester, Salem | 40 min |
| May 9, 7:13 PM EDT | Severe Thunderstorm Warning | PHI | Cape May | 22 min |
| May 9, 7:46 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland | 33 min |
| May 23, 4:40 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Warren | 37 min |
| May 24, 5:16 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 59 min |
| May 24, 7:06 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Somerset | 54 min |
| May 24, 7:56 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Middlesex, Somerset | 30 min |
| May 29, 5:10 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester | 42 min |
| Jun 2, 2:53 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Cumberland, Gloucester, Salem | 67 min |
| Jun 2, 3:38 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland, Salem | 67 min |
| Jun 2, 4:22 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Cumberland, Gloucester, Ocean | 53 min |
| Jun 2, 4:39 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 51 min |
| Jun 3, 4:06 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland, Gloucester, Salem | 54 min |
| Jun 3, 4:55 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cumberland, Salem | 65 min |
| Jun 9, 12:48 AM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex, Warren | 42 min |
| Jun 9, 8:00 AM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Salem | 60 min |
| Jun 9, 8:06 AM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden | 54 min |
| Jun 9, 8:30 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cumberland, Gloucester, Salem | 60 min |
| Jun 9, 8:43 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester | 62 min |
| Jun 9, 8:47 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 70 min |
| Jun 15, 3:17 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 43 min |
| Jun 15, 6:37 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester | 53 min |
| Jun 15, 7:05 PM EDT | Severe Thunderstorm Warning | PHI | Sussex, Warren | 55 min |
| Jun 15, 7:48 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Somerset, Sussex, Warren | 28 min |
| Jun 20, 5:01 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland, Salem | 59 min |
| Jun 20, 6:35 PM EDT | Severe Thunderstorm Warning | PHI | Cape May | 10 min |
| Jun 26, 4:34 PM EDT | Severe Thunderstorm Warning | PHI | Sussex | 86 min |
| Jun 26, 4:45 PM EDT | Severe Thunderstorm Warning | OKX | Passaic | 45 min |
| Jun 26, 4:51 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 69 min |
| Jun 26, 4:55 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 50 min |
| Jun 26, 5:26 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 64 min |
| Jun 26, 5:27 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Somerset | 78 min |
| Jun 26, 6:27 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 45 min |
| Jun 26, 6:41 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Somerset | 41 min |
| Jun 26, 6:45 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth | 30 min |
| Jun 26, 7:10 PM EDT | Severe Thunderstorm Warning | PHI | Burlington | 50 min |
| Jun 26, 7:18 PM EDT | Severe Thunderstorm Warning | PHI | Mercer, Middlesex, Monmouth, Ocean | 72 min |
| Jun 26, 7:28 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Monmouth, Ocean | 92 min |
| Jun 26, 7:45 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester, Ocean | 65 min |
| Jun 26, 9:46 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Monmouth, Ocean | 89 min |
| Jun 30, 3:12 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon | 63 min |
| Jun 30, 4:07 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Passaic | 38 min |
| Jul 1, 6:55 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex, Monmouth, Ocean | 65 min |
| Jul 1, 7:05 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer | 55 min |
| Jul 1, 7:38 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth, Ocean | 67 min |
| Jul 7, 2:29 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Somerset, Warren | 61 min |
| Jul 7, 10:25 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 48 min |
| Jul 7, 11:09 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 56 min |
| Jul 7, 11:29 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 61 min |
| Jul 16, 5:11 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 49 min |
| Jul 16, 5:56 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 64 min |
| Jul 16, 6:42 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden | 63 min |
| Jul 16, 7:05 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Mercer, Monmouth, Ocean | 70 min |
| Jul 17, 5:41 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex, Warren | 52 min |
| Jul 17, 8:51 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Somerset | 54 min |
| Jul 17, 9:21 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex | 54 min |
| Jul 17, 9:44 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Passaic | 46 min |
| Jul 24, 6:28 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 62 min |
| Jul 24, 7:11 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester, Salem | 46 min |
| Jul 24, 10:13 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 47 min |
| Jul 26, 3:29 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth | 61 min |
| Jul 26, 4:06 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Warren | 54 min |
| Jul 26, 5:24 PM EDT | Severe Thunderstorm Warning | OKX | Essex, Union | 66 min |
| Jul 26, 5:51 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 39 min |
| Jul 26, 5:58 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Hudson, Passaic | 32 min |
| Jul 26, 6:26 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Hudson | 34 min |
| Jul 26, 7:07 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth | 53 min |
| Jul 26, 7:40 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Monmouth, Ocean | 65 min |
| Jul 26, 8:16 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex | 59 min |
| Jul 26, 8:54 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 39 min |
| Jul 27, 4:25 PM EDT | Severe Thunderstorm Warning | PHI | Cape May | 54 min |
| Jul 28, 5:09 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Somerset | 51 min |
| Jul 29, 12:54 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Passaic | 66 min |
| Jul 29, 12:55 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Somerset | 65 min |
| Jul 29, 1:35 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Somerset | 55 min |
| Jul 29, 1:48 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 57 min |
| Jul 29, 1:49 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 30 min |
| Jul 29, 1:56 PM EDT | Severe Thunderstorm Warning | PHI | Sussex | 64 min |
| Jul 29, 2:46 PM EDT | Severe Thunderstorm Warning | OKX | Essex, Hudson, Union | 29 min |
| Jul 29, 5:09 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer | 66 min |
| Jul 29, 6:11 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland | 26 min |
| Jul 29, 6:26 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Camden, Gloucester | 38 min |
| Jul 29, 6:42 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden | 39 min |
| Jul 29, 6:49 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Hudson | 29 min |
| Jul 29, 7:31 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth | 30 min |
| Jul 31, 4:03 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 57 min |
| Jul 31, 4:31 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester, Salem | 59 min |
| Jul 31, 4:39 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more | 96 min |
| Jul 31, 5:15 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Ocean | 60 min |
| Aug 2, 10:53 AM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester, Salem | 67 min |
| Aug 2, 11:14 AM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Warren | 61 min |
| Aug 2, 11:25 AM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Mercer | 65 min |
| Aug 2, 11:30 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Camden, Cape May, Cumberland, Gloucester, Salem | 60 min |
| Aug 2, 11:48 AM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Middlesex, Monmouth, Somerset | 57 min |
| Aug 2, 12:27 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Somerset | 48 min |
| Aug 2, 12:41 PM EDT | Severe Thunderstorm Warning | OKX | Union | 34 min |
| Aug 2, 12:45 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth | 60 min |
| Aug 2, 1:05 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 40 min |
| Aug 2, 1:43 PM EDT | Severe Thunderstorm Warning | PHI | Cape May | 47 min |
| Aug 5, 1:46 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex, Warren | 59 min |
| Aug 5, 2:45 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Sussex, Warren | 75 min |
| Aug 9, 6:10 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester, Salem | 80 min |
| Aug 9, 6:48 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Camden, Cumberland, Gloucester, Salem | 72 min |
| Aug 9, 7:21 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Cape May, Cumberland, Ocean | 69 min |
| Aug 10, 7:12 PM EDT | Severe Thunderstorm Warning | PHI | Sussex | 48 min |
| Aug 10, 8:08 PM EDT | Severe Thunderstorm Warning | PHI | Sussex | 37 min |
| Aug 11, 4:19 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 34 min |
| Aug 12, 1:26 PM EDT | Severe Thunderstorm Warning | PHI | Ocean | 22 min |
| Aug 12, 3:01 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cumberland | 59 min |
| Aug 18, 7:22 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 53 min |
| Aug 18, 7:37 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Salem | 68 min |
| Aug 18, 8:21 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester, Ocean | 69 min |
| Aug 18, 8:35 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Hunterdon, Mercer, Middlesex, Monmouth, Ocean and 1 more | 70 min |
| Aug 18, 8:59 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth, Somerset | 60 min |
| Aug 18, 9:43 PM EDT | Severe Thunderstorm Warning | OKX | Essex, Hudson, Union | 47 min |
| Aug 21, 2:34 PM EDT | Severe Thunderstorm Warning | PHI | Sussex | 63 min |
| Aug 21, 3:48 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 27 min |
| Aug 21, 4:13 PM EDT | Severe Thunderstorm Warning | PHI | Salem | 77 min |
| Aug 28, 7:55 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May | 70 min |
| Aug 28, 11:53 AM EDT | Severe Thunderstorm Warning | PHI | Cape May, Cumberland | 43 min |
| Sep 11, 2:48 AM EDT | Severe Thunderstorm Warning | PHI | Cape May | 72 min |
| Sep 11, 3:55 AM EDT | Severe Thunderstorm Warning | PHI | Cape May, Cumberland | 65 min |
| Sep 11, 4:55 AM EDT | Severe Thunderstorm Warning | PHI | Cape May, Cumberland | 65 min |
| Sep 11, 5:36 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 69 min |
| Sep 11, 5:52 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 53 min |
| Sep 11, 6:49 AM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cape May, Cumberland | 86 min |
| Sep 11, 8:46 AM EDT | Severe Thunderstorm Warning | PHI | Monmouth | 39 min |
| Sep 28, 5:47 PM EDT | Severe Thunderstorm Warning | PHI | Burlington | 28 min |
| Oct 24, 6:19 PM EDT | Severe Thunderstorm Warning | PHI | Salem | 26 min |
| Oct 24, 6:28 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Somerset | 47 min |
| Dec 3, 5:41 AM EST | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and 1 more | 49 min |
| Dec 3, 6:33 AM EST | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 42 min |
| Dec 9, 4:42 PM EST | Severe Thunderstorm Warning | OKX | Essex, Passaic | 18 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Burlington County28
- Gloucester County28
- Atlantic County27
- Camden County26
- Cumberland County26
- Salem County25
- Bergen County22
- Mercer County20
- Hunterdon County19
- Cape May County19
- Monmouth County18
- Ocean County18
- Somerset County18
- Passaic County17
- Middlesex County16
- Warren County14
- Sussex County13
- Essex County11
- Morris County10
- Hudson County9
- Union County8
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20082010
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.