Alert archive / Virginia / Clarke County
Weather alerts in Clarke County, Virginia, 2009
98 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Clarke County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 98
- Warnings
- 18
- Watches
- 24
- Advisories
- 33
- Busiest month
- June21 alerts
- Busiest day
- June 9, 20096 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Clarke County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 12 | 9 | 25% | 1 | 100% | 31 min |
| Flash flood warnings | 0 | 0 |
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 5, 4:09 AM EST | Winter Storm Watch | LWX | 11 hr |
| Jan 5, 2:57 PM EST | Winter Weather Advisory | LWX | 45 hr |
| 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 2, 10:49 AM EST | Winter Weather Advisory | LWX | 17 hr |
| Feb 10, 3:52 PM EST | High Wind Watch | LWX | 24 hr |
| Feb 11, 3:40 PM EST | High Wind Warning | LWX | 28 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, 5:32 PM EST | Mesoscale Discussion | SPC | 88 min |
| 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, 8:54 PM EST | Severe Thunderstorm Warning | LWX | 51 min |
| Feb 11, 9:19 PM EST | Severe Thunderstorm Warning | LWX | 36 min |
| Feb 12, 6:49 AM EST | Red Flag Warning | LWX | 14 hr |
| Feb 17, 10:15 PM EST | Winter Weather Advisory | LWX | 14 hr |
| Feb 19, 9:17 PM EST | Wind Chill Advisory | LWX | 12 hr |
| Mar 1, 4:11 AM EST | Winter Weather Advisory | LWX | 31 hr |
| Mar 2, 3:03 PM EST | Wind Chill Advisory | LWX | 18 hr |
| Mar 27, 1:51 AM EDT | Dense Fog Advisory | LWX | 7 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 3, 4:32 AM EDT | Wind Advisory | LWX | 34 hr |
| Apr 21, 6:30 AM EDT | Dense Fog Advisory | LWX | 3 hr |
| Apr 21, 2:12 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| May 4, 8:51 AM EDT | Flood Watch | LWX | 4 hr |
| May 8, 5:35 PM EDT | Flash Flood Watch | LWX | 7 hr |
| May 15, 3:12 AM EDT | Dense Fog Advisory | LWX | 6 hr |
| May 16, 2:36 PM EDT | Mesoscale Discussion | SPC | 24 min |
| May 17, 3:18 AM EDT | Frost Advisory | LWX | 30 hr |
| May 18, 3:53 AM EDT | Frost Advisory | LWX | 28 hr |
| May 28, 4:55 PM EDT | Flash Flood Watch | LWX | 7 hr |
| May 29, 12:20 PM EDT | Mesoscale Discussion | SPC | 55 min |
| 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, 7:10 PM EDT | Mesoscale Discussion | SPC | 95 min |
| Jun 4, 4:28 AM EDT | Flood Watch | LWX | 38 hr |
| 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, 4:10 PM EDT | Severe Thunderstorm Warning | LWX | 50 min |
| Jun 9, 4:21 PM EDT | Severe Thunderstorm Warning | LWX | 39 min |
| Jun 9, 4:52 PM EDT | Severe Thunderstorm Warning | LWX | 53 min |
| Jun 10, 1:57 PM EDT | Mesoscale Discussion | SPC | 93 min |
| Jun 10, 6:12 PM EDT | Severe Thunderstorm Warning | LWX | 48 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, 7:43 PM EDT | Severe Thunderstorm Warning | LWX | 47 min |
| Jun 17, 9:23 PM EDT | Flash Flood Watch | LWX | 7 hr |
| Jun 26, 2:42 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 26, 7:33 PM EDT | Mesoscale Discussion | SPC | 57 min |
| Jun 26, 9:11 PM EDT | Mesoscale Discussion | SPC | 64 min |
| Jul 1, 4:57 PM EDT | Severe Thunderstorm Warning | LWX | 48 min |
| Jul 6, 5:10 AM EDT | Dense Fog Advisory | LWX | 4 hr |
| Jul 17, 10:29 AM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 21, 1:56 PM EDT | Mesoscale Discussion | SPC | 64 min |
| Jul 24, 3:34 PM EDT | Mesoscale Discussion | SPC | 86 min |
| Jul 25, 3:05 PM EDT | Mesoscale Discussion | SPC | 55 min |
| Jul 26, 1:40 PM EDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 26, 3:21 PM EDT | Severe Thunderstorm Warning | LWX | 39 min |
| Jul 26, 3:58 PM EDT | Severe Thunderstorm Warning | LWX | 62 min |
| Aug 21, 5:25 PM EDT | Severe Thunderstorm Warning | LWX | 50 min |
| Aug 21, 5:44 PM EDT | Severe Thunderstorm Warning | LWX | 46 min |
| Aug 21, 7:30 PM EDT | Mesoscale Discussion | SPC | 60 min |
| Oct 6, 10:03 PM EDT | Wind Advisory | LWX | 20 hr |
| Oct 18, 3:41 AM EDT | Freeze Watch | LWX | 11 hr |
| Oct 18, 2:58 PM EDT | Freeze Warning | LWX | 18 hr |
| Oct 19, 2:48 PM EDT | Frost Advisory | LWX | 18 hr |
| Nov 3, 1:35 PM EST | Frost Advisory | LWX | 18 hr |
| Nov 3, 8:24 PM EST | Freeze Warning | LWX | 12 hr |
| Nov 14, 9:06 PM EST | Dense Fog Advisory | LWX | 12 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 7, 2:16 PM EST | Winter Storm Watch | LWX | 24 hr |
| Dec 8, 10:09 AM EST | Flood Watch | LWX | 21 hr |
| Dec 8, 2:30 PM EST | Winter Weather Advisory | LWX | 17 hr |
| Dec 9, 4:02 AM EST | Wind Advisory | LWX | 17 hr |
| Dec 12, 3:21 PM EST | Winter Weather Advisory | LWX | 23 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 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 23, 2:46 PM EST | Winter Storm Watch | LWX | 24 hr |
| Dec 24, 2:29 PM EST | Winter Weather Advisory | LWX | 31 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 27, 1:12 AM EST | Dense Fog Advisory | LWX | 8 hr |
| Dec 28, 2:48 PM EST | Wind Advisory | LWX | 23 hr |
| Dec 30, 1:58 PM EST | Winter Weather Advisory | LWX | 21 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 | 12 |
| Severe Thunderstorm Watch | 6 |
| Mesoscale Discussion | 23 |
| Flooding | |
| Flash Flood Watch | 5 |
| Flood Watch | 5 |
| Winter | |
| Winter Storm Warning | 2 |
| Winter Storm Watch | 5 |
| Winter Weather Advisory | 11 |
| Cold | |
| Freeze Warning | 2 |
| Freeze Watch | 1 |
| Frost Advisory | 4 |
| Wind Chill Advisory | 3 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 1 |
| Wind Advisory | 5 |
| Fire | |
| Red Flag Warning | 1 |
| Fire Weather Watch | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 10 |
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.