Alert archive / Connecticut / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in Connecticut, 2009
104 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
- 104
- Busiest month
- July49 severe thunderstorm warnings
- Busiest day
- May 24, 200914 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.
58 of 104 severe thunderstorm warnings covering Connecticut in 2009 had a qualifying storm report inside them; 130 of 158 hail, wind and damage reports fell inside a warning, on average 25 minutes after it went out.
Connecticut, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 104 | 58 | 44% | 158 | 82% | 25 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 Boston/Norton, MA: severe thunderstorm warnings | 114 | 66 | 42% | 250 | 78% | 21 min |
| NWS Albany, NY: severe thunderstorm warnings | 149 | 75 | 50% | 182 | 91% | 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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 29, 8:28 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 62 min |
| May 12, 1:04 PM EDT | Severe Thunderstorm Warning | OKX | Southeastern Connecticut Planning Region | 41 min |
| May 12, 1:28 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Southeastern Connecticut Planning Region | 18 min |
| May 24, 2:25 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region, Northeastern Connecticut Planning Region | 35 min |
| May 24, 2:32 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 43 min |
| May 24, 3:02 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 43 min |
| May 24, 3:22 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 53 min |
| May 24, 3:35 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 40 min |
| May 24, 3:44 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 46 min |
| May 24, 4:07 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 18 min |
| May 24, 4:20 PM EDT | Severe Thunderstorm Warning | OKX | Naugatuck Valley Planning Region | 40 min |
| May 24, 4:53 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 25 min |
| May 24, 5:03 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 42 min |
| May 24, 5:39 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 51 min |
| May 24, 5:55 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 65 min |
| May 24, 6:16 PM EDT | Severe Thunderstorm Warning | OKX | Southeastern Connecticut Planning Region | 44 min |
| May 24, 7:16 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 44 min |
| Jun 26, 3:48 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 57 min |
| Jun 26, 4:00 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 45 min |
| Jun 26, 4:13 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 48 min |
| Jun 26, 4:37 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 53 min |
| Jun 26, 4:41 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 49 min |
| Jun 26, 4:45 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 21 min |
| Jun 26, 4:53 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 52 min |
| Jun 26, 4:55 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 65 min |
| Jun 26, 4:55 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 50 min |
| Jun 26, 4:58 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Southeastern Connecticut Planning Region | 62 min |
| Jun 26, 5:17 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 43 min |
| Jun 26, 5:31 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 44 min |
| Jun 26, 5:59 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 31 min |
| Jun 27, 5:32 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region | 43 min |
| Jun 27, 6:20 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 55 min |
| Jun 27, 6:37 PM EDT | Severe Thunderstorm Warning | BOX | 53 min | |
| Jun 27, 7:09 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 51 min |
| Jun 27, 7:42 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 48 min |
| Jun 27, 7:50 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 55 min |
| Jun 30, 8:24 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 36 min |
| Jun 30, 8:42 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 33 min |
| Jul 1, 10:27 AM EDT | Severe Thunderstorm Warning | OKX | Southeastern Connecticut Planning Region | 63 min |
| Jul 1, 10:49 AM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Southeastern Connecticut Planning Region | 56 min |
| Jul 1, 12:23 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 40 min |
| Jul 1, 3:30 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 42 min |
| Jul 3, 4:02 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region | 43 min |
| Jul 3, 5:31 PM EDT | Severe Thunderstorm Warning | OKX | Naugatuck Valley Planning Region | 44 min |
| Jul 3, 5:53 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region | 37 min |
| Jul 7, 12:52 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 55 min |
| Jul 7, 1:00 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 45 min |
| Jul 7, 1:10 PM EDT | Severe Thunderstorm Warning | OKX | Naugatuck Valley Planning Region | 65 min |
| Jul 7, 1:46 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 44 min |
| Jul 7, 1:58 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region | 62 min |
| Jul 7, 2:10 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 47 min |
| Jul 7, 2:41 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 64 min |
| Jul 7, 11:09 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 56 min |
| Jul 7, 11:29 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 61 min |
| Jul 16, 6:59 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 61 min |
| Jul 16, 7:58 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 62 min |
| Jul 16, 8:24 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 66 min |
| Jul 16, 8:47 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region | 58 min |
| Jul 16, 9:28 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 39 min |
| Jul 17, 3:17 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 58 min |
| Jul 17, 3:44 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 46 min |
| Jul 17, 4:08 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 37 min |
| Jul 17, 4:15 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 60 min |
| Jul 17, 11:01 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 59 min |
| Jul 17, 11:01 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 44 min |
| Jul 17, 11:15 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 24 min |
| Jul 17, 11:40 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 44 min |
| Jul 26, 3:37 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 23 min |
| Jul 26, 6:34 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 11 min |
| Jul 26, 6:40 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 65 min |
| Jul 26, 7:27 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 33 min |
| Jul 26, 8:07 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 38 min |
| Jul 26, 11:57 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 33 min |
| Jul 27, 12:01 AM EDT | Severe Thunderstorm Warning | OKX | Southeastern Connecticut Planning Region | 29 min |
| Jul 27, 12:38 AM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 22 min |
| Jul 27, 2:49 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 71 min |
| Jul 27, 4:22 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 38 min |
| Jul 31, 2:30 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 60 min |
| Jul 31, 2:36 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 54 min |
| Jul 31, 3:25 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 25 min |
| Jul 31, 3:33 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region | 57 min |
| Jul 31, 3:41 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 34 min |
| Jul 31, 4:27 PM EDT | Severe Thunderstorm Warning | OKX | Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region | 63 min |
| Jul 31, 4:33 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 42 min |
| Jul 31, 4:50 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 55 min |
| Aug 5, 3:59 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 29 min |
| Aug 10, 8:31 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 44 min |
| Aug 10, 8:46 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 59 min |
| Aug 10, 9:06 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 42 min |
| Aug 10, 9:11 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 32 min |
| Aug 10, 9:52 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 33 min |
| Aug 21, 3:26 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 79 min |
| Aug 21, 3:36 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 28 min |
| Aug 21, 3:51 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 24 min |
| Aug 21, 4:02 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 58 min |
| Aug 21, 4:09 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 66 min |
| Aug 21, 4:13 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 47 min |
| Aug 21, 4:30 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 75 min |
| Aug 21, 4:36 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 54 min |
| Aug 21, 5:16 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region | 59 min |
| Aug 21, 6:05 PM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region, Northeastern Connecticut Planning Region | 55 min |
| Aug 22, 5:55 AM EDT | Severe Thunderstorm Warning | BOX | Capitol Planning Region, Northeastern Connecticut Planning Region | 50 min |
| Aug 23, 6:03 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 32 min |
| Oct 3, 7:40 PM EDT | Severe Thunderstorm Warning | OKX | Naugatuck Valley Planning Region | 20 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
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.