Alert archive / Virginia / Arlington County
Weather alerts in Arlington County, Virginia, 2009
132 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Arlington County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 132
- Warnings
- 20
- Watches
- 33
- Advisories
- 41
- Busiest month
- June34 alerts
- Busiest day
- June 3, 20097 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Arlington County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 6 | 6 | 0% | 0 | ||
| Flash flood warnings | 4 | 3 | 25% | 1 | 100% | 30 min |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Baltimore/Washington: tornado warnings | 13 | 1 | 92% | 8 | 13% | 2 min |
| NWS Baltimore/Washington: severe thunderstorm warnings | 216 | 113 | 48% | 277 | 86% | 21 min |
| NWS Baltimore/Washington: flash flood warnings | 43 | 18 | 58% | 56 | 80% | 56 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 15, 3:05 PM EST | Wind Chill Advisory | LWX | 25 hr |
| Jan 18, 11:07 AM EST | Winter Weather Advisory | LWX | 33 hr |
| Jan 26, 3:54 AM EST | Winter Storm Watch | LWX | 24 hr |
| Jan 26, 3:07 PM EST | Winter Weather Advisory | LWX | 45 hr |
| Jan 27, 3:45 AM EST | Winter Storm Warning | LWX | 36 hr |
| Feb 3, 4:11 AM EST | Winter Weather Advisory | LWX | 30 hr |
| Feb 11, 3:40 PM EST | Wind Advisory | LWX | 32 hr |
| Feb 11, 3:43 PM EST | Fire Weather Watch | LWX | 15 hr |
| Feb 11, 8:00 PM EST | Mesoscale Discussion | SPC | 60 min |
| Feb 11, 8:19 PM EST | Severe Thunderstorm Watch | SPC | 3 hr |
| Feb 11, 10:07 PM EST | Severe Thunderstorm Warning | LWX | 49 min |
| Feb 11, 10:14 PM EST | Mesoscale Discussion | SPC | 61 min |
| Feb 12, 6:49 AM EST | Red Flag Warning | LWX | 14 hr |
| Feb 28, 3:58 AM EST | Winter Storm Watch | LWX | 24 hr |
| Mar 1, 4:11 AM EST | Winter Storm Warning | LWX | 34 hr |
| Mar 1, 5:01 PM EST | Mesoscale Discussion | SPC | 2 hr |
| Mar 2, 3:03 PM EST | Wind Chill Advisory | LWX | 18 hr |
| Mar 18, 6:19 AM EDT | Dense Fog Advisory | LWX | 4 hr |
| Mar 29, 1:49 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Apr 2, 3:35 AM EDT | Dense Fog Advisory | LWX | 6 hr |
| Apr 16, 3:27 PM EDT | Frost Advisory | LWX | 16 hr |
| Apr 21, 6:31 PM EDT | Severe Thunderstorm Warning | LWX | 44 min |
| May 6, 3:11 PM EDT | Coastal Flood Advisory | LWX | 7 hr |
| May 7, 12:22 AM EDT | Areal Flood Warning | LWX | 3 hr |
| May 7, 8:36 AM EDT | Coastal Flood Advisory | LWX | 3 hr |
| May 7, 7:03 PM EDT | Coastal Flood Advisory | LWX | 4 hr |
| May 8, 3:42 AM EDT | Coastal Flood Advisory | LWX | 8 hr |
| May 16, 2:36 PM EDT | Mesoscale Discussion | SPC | 24 min |
| May 26, 7:15 AM EDT | Flash Flood Warning | LWX | 4 hr |
| May 26, 7:27 AM EDT | Flash Flood Warning | LWX | 4 hr |
| May 26, 11:38 AM EDT | Flood Watch | LWX | 7 hr |
| May 28, 4:55 PM EDT | Flash Flood Watch | LWX | 7 hr |
| May 29, 12:14 AM EDT | Flash Flood Watch | LWX | 4 hr |
| May 29, 4:22 AM EDT | Flash Flood Watch | LWX | 15 hr |
| May 29, 12:20 PM EDT | Mesoscale Discussion | SPC | 55 min |
| May 29, 1:26 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
| May 29, 4:30 PM EDT | Mesoscale Discussion | SPC | 60 min |
| May 29, 6:20 PM EDT | Mesoscale Discussion | SPC | 55 min |
| Jun 2, 1:31 PM EDT | Mesoscale Discussion | SPC | 89 min |
| Jun 2, 1:58 PM EDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 2, 4:18 PM EDT | Mesoscale Discussion | SPC | 87 min |
| Jun 3, 4:39 AM EDT | Flash Flood Watch | LWX | 20 hr |
| Jun 3, 12:41 PM EDT | Mesoscale Discussion | SPC | 64 min |
| Jun 3, 1:06 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 3, 4:34 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Jun 3, 6:44 PM EDT | Severe Thunderstorm Warning | LWX | 46 min |
| Jun 3, 7:10 PM EDT | Mesoscale Discussion | SPC | 95 min |
| Jun 3, 7:33 PM EDT | Flash Flood Warning | LWX | 3 hr |
| Jun 4, 4:28 AM EDT | Flood Watch | LWX | 38 hr |
| Jun 5, 9:58 AM EDT | Areal Flood Warning | LWX | 6 hr |
| Jun 9, 5:47 AM EDT | Severe Thunderstorm Warning | LWX | 28 min |
| Jun 9, 6:01 AM EDT | Mesoscale Discussion | SPC | 59 min |
| Jun 9, 1:18 PM EDT | Flash Flood Watch | LWX | 7 hr |
| Jun 9, 2:07 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 9, 4:03 PM EDT | Mesoscale Discussion | SPC | 57 min |
| Jun 9, 5:13 PM EDT | Severe Thunderstorm Warning | LWX | 62 min |
| Jun 10, 1:57 PM EDT | Mesoscale Discussion | SPC | 93 min |
| Jun 10, 9:06 PM EDT | Flash Flood Warning | LWX | 90 min |
| Jun 11, 3:58 AM EDT | Flash Flood Watch | LWX | 24 hr |
| Jun 11, 11:51 AM EDT | Mesoscale Discussion | SPC | 84 min |
| Jun 11, 1:59 PM EDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jun 13, 8:09 PM EDT | Mesoscale Discussion | SPC | 66 min |
| Jun 16, 4:11 AM EDT | Coastal Flood Advisory | LWX | 3 days |
| Jun 17, 3:26 AM EDT | Coastal Flood Watch | LWX | 12 hr |
| Jun 18, 11:40 AM EDT | Mesoscale Discussion | SPC | 95 min |
| Jun 18, 2:21 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 20, 1:55 PM EDT | Mesoscale Discussion | SPC | 95 min |
| Jun 24, 3:49 AM EDT | Coastal Flood Advisory | LWX | 7 hr |
| Jun 26, 2:42 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 26, 7:15 PM EDT | Severe Thunderstorm Warning | LWX | 45 min |
| Jun 26, 7:33 PM EDT | Mesoscale Discussion | SPC | 57 min |
| Jun 26, 9:11 PM EDT | Mesoscale Discussion | SPC | 64 min |
| Jul 17, 9:52 AM EDT | Mesoscale Discussion | SPC | 83 min |
| Jul 17, 10:29 AM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 17, 12:59 PM EDT | Mesoscale Discussion | SPC | 91 min |
| Jul 24, 3:34 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Jul 26, 1:40 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 26, 2:07 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 26, 4:16 PM EDT | Mesoscale Discussion | SPC | 89 min |
| Jul 29, 1:32 PM EDT | Mesoscale Discussion | SPC | 28 min |
| Jul 31, 12:06 PM EDT | Mesoscale Discussion | SPC | 84 min |
| Jul 31, 1:18 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 31, 3:05 PM EDT | Mesoscale Discussion | SPC | 85 min |
| Aug 2, 4:06 AM EDT | Flash Flood Watch | LWX | 10 hr |
| Aug 9, 3:31 PM EDT | Heat Advisory | LWX | 28 hr |
| Aug 21, 12:16 PM EDT | Mesoscale Discussion | SPC | 119 min |
| Aug 21, 12:36 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 21, 7:30 PM EDT | Mesoscale Discussion | SPC | 60 min |
| Aug 22, 4:06 AM EDT | Flash Flood Watch | LWX | 19 hr |
| Aug 28, 5:50 AM EDT | Flash Flood Watch | LWX | 22 hr |
| Sep 8, 11:19 AM EDT | Coastal Flood Advisory | LWX | 17 hr |
| Sep 10, 4:36 AM EDT | Coastal Flood Advisory | LWX | 21 hr |
| Sep 17, 2:16 PM EDT | Coastal Flood Advisory | LWX | 32 hr |
| Sep 26, 3:58 PM EDT | Coastal Flood Advisory | LWX | 12 hr |
| Sep 27, 4:09 AM EDT | Coastal Flood Advisory | LWX | 13 hr |
| Oct 6, 10:03 PM EDT | Wind Advisory | LWX | 20 hr |
| Oct 15, 3:10 PM EDT | Coastal Flood Advisory | LWX | 54 hr |
| Oct 19, 2:48 PM EDT | Frost Advisory | LWX | 18 hr |
| Oct 24, 12:19 PM EDT | Mesoscale Discussion | SPC | 116 min |
| Oct 29, 10:18 PM EDT | Coastal Flood Advisory | LWX | 49 hr |
| Nov 3, 1:24 PM EST | Coastal Flood Advisory | LWX | 11 hr |
| Nov 5, 2:56 PM EST | Freeze Watch | LWX | 13 hr |
| Nov 6, 3:27 AM EST | Freeze Warning | LWX | 29 hr |
| Nov 11, 4:31 AM EST | Coastal Flood Watch | LWX | 47 hr |
| Nov 11, 9:48 PM EST | Coastal Flood Advisory | LWX | 71 hr |
| Nov 15, 9:48 AM EST | Coastal Flood Advisory | LWX | 11 hr |
| Nov 18, 3:12 PM EST | Coastal Flood Advisory | LWX | 31 hr |
| Nov 25, 7:20 PM EST | Dense Fog Advisory | LWX | 17 hr |
| Dec 2, 1:38 PM EST | Flood Watch | LWX | 14 hr |
| Dec 4, 2:17 PM EST | Winter Weather Advisory | LWX | 30 hr |
| Dec 8, 10:09 AM EST | Flood Watch | LWX | 21 hr |
| Dec 9, 4:02 AM EST | Wind Advisory | LWX | 17 hr |
| Dec 9, 5:15 AM EST | Areal Flood Warning | LWX | 2 hr |
| Dec 9, 9:20 AM EST | Coastal Flood Advisory | LWX | 20 hr |
| Dec 13, 7:55 PM EST | Dense Fog Advisory | LWX | 13 hr |
| Dec 17, 1:48 PM EST | Winter Storm Watch | LWX | 14 hr |
| Dec 18, 4:05 AM EST | Winter Storm Warning | LWX | 47 hr |
| Dec 18, 7:22 PM EST | Mesoscale Discussion | SPC | 5 hr |
| Dec 18, 11:06 PM EST | Blizzard Warning | LWX | 16 hr |
| Dec 19, 12:34 AM EST | Mesoscale Discussion | SPC | 5 hr |
| Dec 19, 6:57 AM EST | Mesoscale Discussion | SPC | 6 hr |
| Dec 19, 12:27 PM EST | Mesoscale Discussion | SPC | 6 hr |
| Dec 24, 2:30 PM EST | Flood Watch | LWX | 36 hr |
| Dec 25, 4:14 PM EST | Dense Fog Advisory | LWX | 4 hr |
| Dec 26, 2:18 AM EST | Coastal Flood Advisory | LWX | 10 hr |
| Dec 26, 9:14 AM EST | Coastal Flood Warning | LWX | 9 hr |
| Dec 26, 5:47 PM EST | Coastal Flood Advisory | LWX | 11 hr |
| Dec 27, 4:09 PM EST | Coastal Flood Advisory | LWX | 5 hr |
| Dec 27, 8:43 PM EST | Coastal Flood Advisory | LWX | 18 hr |
| Dec 28, 2:48 PM EST | Wind Advisory | LWX | 23 hr |
| Dec 30, 1:58 PM EST | Winter Weather Advisory | LWX | 21 hr |
| Dec 30, 10:57 PM EST | Mesoscale Discussion | SPC | 6 hr |
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 | 6 |
| Severe Thunderstorm Watch | 12 |
| Mesoscale Discussion | 38 |
| Flooding | |
| Areal Flood Warning | 3 |
| Flash Flood Warning | 4 |
| Flash Flood Watch | 9 |
| Flood Watch | 5 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 3 |
| Winter Weather Advisory | 5 |
| Heat | |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 1 |
| Freeze Watch | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 2 |
| Wind and dust | |
| Wind Advisory | 4 |
| Fire | |
| Red Flag Warning | 1 |
| Fire Weather Watch | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 5 |
| Coast and beach | |
| Coastal Flood Warning | 1 |
| Coastal Flood Watch | 2 |
| Coastal Flood Advisory | 22 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe 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.