Alert archive / Georgia / Gwinnett County
Weather alerts in Gwinnett County, Georgia, 2021
122 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Gwinnett County and its neighbors
Each county as a circle sized by its count in 2021. Tap one for its archive.
- Alerts
- 122
- Warnings
- 38
- Watches
- 19
- Advisories
- 22
- Busiest month
- May22 alerts
- Busiest day
- May 3, 202112 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Gwinnett County, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 14 | 10 | 29% | 16 | 56% | 20 min |
| Flash flood warnings | 7 | 4 | 43% | 3 | 33% | 53 min |
Each office's whole area, 2021
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Atlanta, GA: tornado warnings | 48 | 14 | 71% | 41 | 54% | 10 min |
| NWS Atlanta, GA: severe thunderstorm warnings | 183 | 100 | 45% | 442 | 59% | 16 min |
| NWS Atlanta, GA: flash flood warnings | 56 | 38 | 32% | 244 | 70% | 167 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 | Lasted |
|---|---|---|---|
| Jan 1, 1:26 AM EST | Dense Fog Advisory | FFC | 9 hr |
| Jan 2, 12:44 AM EST | Dense Fog Advisory | FFC | 9 hr |
| Jan 13, 2:03 AM EST | Freezing Fog Advisory | FFC | 7 hr |
| Feb 1, 4:33 AM EST | Wind Advisory | FFC | 38 hr |
| Feb 6, 3:42 AM EST | Winter Weather Advisory | FFC | 24 hr |
| Feb 9, 10:45 PM EST | Dense Fog Advisory | FFC | 12 hr |
| Feb 12, 4:38 AM EST | Dense Fog Advisory | FFC | 5 hr |
| Feb 17, 2:20 PM EST | Flash Flood Watch | FFC | 29 hr |
| Mar 1, 5:47 AM EST | Special Weather Statement | FFC | 43 min |
| Mar 17, 2:22 AM EDT | Dense Fog Advisory | FFC | 9 hr |
| Mar 18, 4:09 AM EDT | Wind Advisory | FFC | 16 hr |
| Mar 18, 2:38 PM EDT | River Flood Warning | FFC | 3 hr |
| Mar 18, 10:35 PM EDT | River Flood Warning | FFC | 6 hr |
| Mar 25, 1:30 PM EDT | Severe Thunderstorm Warning | FFC | 45 min |
| Mar 25, 7:46 PM EDT | Tornado Watch | SPC | 8 hr |
| Mar 26, 12:34 AM EDT | Mesoscale Discussion | SPC | 56 min |
| Mar 26, 1:55 AM EDT | Tornado Watch | SPC | 3 hr |
| Mar 26, 2:38 AM EDT | Severe Thunderstorm Warning | FFC | 37 min |
| Mar 28, 10:14 AM EDT | Mesoscale Discussion | SPC | 61 min |
| Mar 28, 11:16 AM EDT | Special Weather Statement | FFC | 29 min |
| Mar 31, 9:38 AM EDT | Special Weather Statement | FFC | 37 min |
| Mar 31, 4:22 PM EDT | Freeze Watch | FFC | 11 hr |
| Mar 31, 4:22 PM EDT | Wind Advisory | FFC | 27 hr |
| Apr 1, 2:52 AM EDT | Freeze Warning | FFC | 31 hr |
| Apr 1, 3:14 PM EDT | Freeze Watch | FFC | 21 hr |
| Apr 2, 11:49 AM EDT | Freeze Warning | FFC | 22 hr |
| Apr 3, 2:49 PM EDT | Frost Advisory | FFC | 18 hr |
| Apr 20, 2:39 PM EDT | Fire Weather Watch | FFC | 15 hr |
| Apr 20, 2:41 PM EDT | Wind Advisory | FFC | 31 hr |
| Apr 24, 5:09 PM EDT | Severe Thunderstorm Warning | FFC | 51 min |
| Apr 24, 5:52 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Apr 24, 5:53 PM EDT | Special Weather Statement | FFC | 52 min |
| Apr 24, 7:13 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 24, 8:07 PM EDT | Severe Thunderstorm Warning | FFC | 53 min |
| Apr 24, 8:36 PM EDT | Severe Thunderstorm Warning | FFC | 39 min |
| Apr 24, 9:03 PM EDT | Severe Thunderstorm Warning | FFC | 42 min |
| May 3, 10:04 AM EDT | Mesoscale Discussion | SPC | 86 min |
| May 3, 10:29 AM EDT | Tornado Watch | SPC | 5 hr |
| May 3, 11:10 AM EDT | Severe Thunderstorm Warning | FFC | 32 min |
| May 3, 11:20 AM EDT | Mesoscale Discussion | SPC | 55 min |
| May 3, 11:38 AM EDT | Severe Thunderstorm Warning | FFC | 37 min |
| May 3, 11:53 AM EDT | Severe Thunderstorm Warning | FFC | 37 min |
| May 3, 12:28 PM EDT | Flash Flood Warning | FFC | 8 hr |
| May 3, 1:03 PM EDT | Mesoscale Discussion | SPC | 87 min |
| May 3, 3:05 PM EDT | Mesoscale Discussion | SPC | 55 min |
| May 3, 3:23 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 3, 5:29 PM EDT | River Flood Warning | FFC | 7 hr |
| May 3, 5:40 PM EDT | Flash Flood Watch | FFC | 32 hr |
| May 3, 8:01 PM EDT | River Flood Warning | FFC | 2 hr |
| May 4, 4:34 AM EDT | River Flood Warning | FFC | 5 hr |
| May 4, 10:48 AM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| May 4, 1:21 PM EDT | Mesoscale Discussion | SPC | 114 min |
| May 4, 1:48 PM EDT | Special Weather Statement | FFC | 27 min |
| May 4, 1:52 PM EDT | Severe Thunderstorm Warning | FFC | 38 min |
| May 4, 3:07 PM EDT | Mesoscale Discussion | SPC | 113 min |
| May 4, 3:08 PM EDT | Flash Flood Warning | FFC | 7 hr |
| May 5, 2:42 AM EDT | River Flood Warning | FFC | 4 hr |
| May 5, 6:36 AM EDT | River Flood Warning | FFC | 9 hr |
| Jun 14, 4:52 PM EDT | Severe Thunderstorm Warning | FFC | 38 min |
| Jun 18, 3:46 AM EDT | Flash Flood Watch | FFC | 59 hr |
| Jun 30, 6:46 PM EDT | Special Weather Statement | FFC | 14 min |
| Jul 9, 2:40 PM EDT | Severe Thunderstorm Warning | FFC | 35 min |
| Jul 9, 2:47 PM EDT | Special Weather Statement | FFC | 28 min |
| Jul 9, 3:03 PM EDT | Special Weather Statement | FFC | 27 min |
| Jul 12, 2:48 PM EDT | Special Weather Statement | FFC | 42 min |
| Jul 12, 8:08 PM EDT | Special Weather Statement | FFC | 37 min |
| Jul 20, 3:21 AM EDT | Flash Flood Watch | FFC | 19 hr |
| Jul 21, 9:49 PM EDT | Special Weather Statement | FFC | 41 min |
| Jul 21, 10:21 PM EDT | Flash Flood Warning | FFC | 6 hr |
| Jul 22, 12:29 AM EDT | River Flood Warning | FFC | 107 min |
| Jul 24, 9:29 PM EDT | Special Weather Statement | FFC | 31 min |
| Jul 24, 10:07 PM EDT | Flash Flood Warning | FFC | 6 hr |
| Jul 25, 3:43 AM EDT | River Flood Warning | FFC | 4 hr |
| Jul 25, 9:25 AM EDT | River Flood Warning | FFC | 11 hr |
| Jul 26, 8:18 PM EDT | Special Weather Statement | FFC | 27 min |
| Jul 26, 8:46 PM EDT | Special Weather Statement | FFC | 29 min |
| Jul 27, 5:11 PM EDT | Severe Thunderstorm Warning | FFC | 34 min |
| Jul 27, 6:29 PM EDT | Special Weather Statement | FFC | 31 min |
| Jul 29, 5:32 AM EDT | Heat Advisory | FFC | 14 hr |
| Jul 29, 10:36 AM EDT | Heat Advisory | FFC | 33 hr |
| Jul 30, 2:50 PM EDT | Heat Advisory | FFC | 29 hr |
| Aug 7, 5:22 PM EDT | Special Weather Statement | FFC | 23 min |
| Aug 7, 6:01 PM EDT | Special Weather Statement | FFC | 29 min |
| Aug 10, 5:59 PM EDT | Special Weather Statement | FFC | 31 min |
| Aug 10, 6:09 PM EDT | Severe Thunderstorm Warning | FFC | 36 min |
| Aug 11, 2:48 PM EDT | Special Weather Statement | FFC | 27 min |
| Aug 16, 4:32 AM EDT | Flash Flood Watch | FFC | 40 hr |
| Aug 17, 3:45 AM EDT | Tornado Watch | SPC | 9 hr |
| Aug 17, 8:31 AM EDT | River Flood Warning | FFC | 5 hr |
| Aug 17, 8:40 AM EDT | Flash Flood Warning | FFC | 6 hr |
| Aug 19, 4:04 PM EDT | Special Weather Statement | FFC | 26 min |
| Aug 19, 4:35 PM EDT | Special Weather Statement | FFC | 25 min |
| Aug 19, 5:32 PM EDT | River Flood Warning | FFC | 112 min |
| Aug 27, 7:19 PM EDT | Special Weather Statement | FFC | 11 min |
| Aug 31, 8:44 AM EDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 31, 2:03 PM EDT | Mesoscale Discussion | SPC | 117 min |
| Sep 7, 11:47 PM EDT | Flash Flood Warning | FFC | 9 hr |
| Sep 8, 12:04 AM EDT | Special Weather Statement | FFC | 26 min |
| Sep 8, 1:13 AM EDT | River Flood Warning | FFC | 4 hr |
| Sep 8, 5:17 PM EDT | Special Weather Statement | FFC | 43 min |
| Sep 8, 6:16 PM EDT | Flash Flood Warning | FFC | 6 hr |
| Sep 20, 2:50 PM EDT | River Flood Warning | FFC | 3 hr |
| Oct 4, 11:04 AM EDT | Flash Flood Watch | FFC | 4 days |
| Oct 6, 2:26 PM EDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 7, 5:31 PM EDT | Special Weather Statement | FFC | 119 min |
| Oct 13, 8:50 AM EDT | Dense Fog Advisory | FFC | 2 hr |
| Nov 12, 4:30 AM EST | Freeze Watch | FFC | 26 hr |
| Nov 13, 6:02 AM EST | Freeze Warning | FFC | 27 hr |
| Nov 14, 2:36 PM EST | Frost Advisory | FFC | 16 hr |
| Dec 10, 4:44 PM EST | Dense Fog Advisory | FFC | 17 hr |
| Dec 11, 1:40 PM EST | Special Weather Statement | FFC | 35 min |
| Dec 11, 2:22 PM EST | Special Weather Statement | FFC | 38 min |
| Dec 16, 9:33 PM EST | Dense Fog Advisory | FFC | 12 hr |
| Dec 17, 10:06 AM EST | Dense Fog Advisory | FFC | 114 min |
| Dec 26, 9:22 PM EST | Dense Fog Advisory | FFC | 13 hr |
| Dec 29, 9:44 PM EST | Mesoscale Discussion | SPC | 2 hr |
| Dec 29, 10:16 PM EST | Tornado Watch | SPC | 7 hr |
| Dec 29, 11:42 PM EST | Special Weather Statement | FFC | 33 min |
| Dec 29, 11:56 PM EST | Mesoscale Discussion | SPC | 2 hr |
| Dec 30, 8:35 AM EST | Flood Watch | FFC | 10 hr |
| Dec 31, 3:48 AM EST | Dense Fog Advisory | FFC | 6 hr |
| Dec 31, 6:40 PM EST | Mesoscale Discussion | SPC | 95 min |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
| Product | Alerts |
|---|---|
| Severe storms | |
| Severe Thunderstorm Warning | 14 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 5 |
| Mesoscale Discussion | 15 |
| Special Weather Statement | 28 |
| Flooding | |
| Flash Flood Warning | 7 |
| River Flood Warning | 14 |
| Flash Flood Watch | 6 |
| Flood Watch | 1 |
| Winter | |
| Winter Weather Advisory | 1 |
| Heat | |
| Heat Advisory | 3 |
| Cold | |
| Freeze Warning | 3 |
| Freeze Watch | 3 |
| Frost Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fire | |
| Fire Weather Watch | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 11 |
| Freezing Fog Advisory | 1 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20202022
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.