Weather alerts in West Virginia, 2010
1,547 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.
Weather alerts by county
Each county as a circle sized by its count in 2010. Tap one for its archive.
- Alerts
- 1,547
- Warnings
- 564
- Watches
- 190
- Advisories
- 218
- Busiest month
- June290 alerts
- Busiest day
- July 25, 201048 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
2 of 13 tornado warnings covering West Virginia in 2010 had a tornado report inside them; 6 of 7 tornado reports fell inside a warning, on average 24 minutes after it went out.
West Virginia, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 13 | 2 | 85% | 7 | 86% | 24 min |
| Severe thunderstorm warnings | 269 | 183 | 32% | 295 | 83% | 25 min |
| Flash flood warnings | 85 | 46 | 46% | 115 | 86% | 91 min |
Each office's whole area, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Baltimore/Washington: tornado warnings | 31 | 2 | 94% | 4 | 50% | 17 min |
| NWS Baltimore/Washington: severe thunderstorm warnings | 257 | 198 | 23% | 762 | 86% | 21 min |
| NWS Baltimore/Washington: flash flood warnings | 64 | 35 | 45% | 139 | 92% | 166 min |
| NWS Pittsburgh, PA: tornado warnings | 13 | 1 | 92% | 4 | 25% | 4 min |
| NWS Pittsburgh, PA: severe thunderstorm warnings | 204 | 124 | 39% | 290 | 82% | 26 min |
| NWS Pittsburgh, PA: flash flood warnings | 24 | 15 | 38% | 29 | 90% | 73 min |
| NWS Blacksburg, VA: tornado warnings | 31 | 2 | 94% | 7 | 43% | 3 min |
| NWS Blacksburg, VA: severe thunderstorm warnings | 344 | 275 | 20% | 845 | 76% | 23 min |
| NWS Blacksburg, VA: flash flood warnings | 111 | 62 | 44% | 205 | 90% | 130 min |
| NWS Charleston, WV: tornado warnings | 11 | 4 | 64% | 16 | 69% | 26 min |
| NWS Charleston, WV: severe thunderstorm warnings | 135 | 87 | 36% | 292 | 79% | 25 min |
| NWS Charleston, WV: flash flood warnings | 58 | 30 | 48% | 120 | 86% | 100 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
1,547 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Mercer County191
- Grant County178
- Summers County175
- Mineral County168
- Jefferson County168
- Monroe County167
- Berkeley County150
- Hancock County148
- Hardy County143
- Hampshire County139
- Kanawha County138
- Jackson County134
- Morgan County132
- Mason County132
- Brooke County132
- Marshall County132
- Cabell County129
- Wayne County129
- Ohio County127
- Lincoln County126
- Putnam County126
- Roane County120
- Wetzel County120
- Greenbrier County119
- Boone County116
- Logan County113
- Wyoming County112
- Wood County112
- Clay County109
- Ritchie County109
- Barbour County108
- McDowell County108
- Pendleton County107
- Doddridge County106
- Pleasants County106
- Marion County105
- Upshur County104
- Gilmer County104
- Tyler County104
- Calhoun County103
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20092011
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.