Alert archive / North Carolina / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in North Carolina, 2008
1,204 severe thunderstorm warnings in 2008. 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 2008. Tap one for its archive.
- Severe Thunderstorm Warnings
- 1,204
- Busiest month
- July337 severe thunderstorm warnings
- Busiest day
- May 20, 200870 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.
604 of 1,204 severe thunderstorm warnings covering North Carolina in 2008 had a qualifying storm report inside them; 897 of 1,116 hail, wind and damage reports fell inside a warning, on average 23 minutes after it went out.
North Carolina, 2008
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Severe thunderstorm warnings | 1,204 | 604 | 50% | 1,116 | 80% | 23 min |
Each office's whole area, 2008
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Morristown, TN: severe thunderstorm warnings | 298 | 230 | 23% | 400 | 87% | 21 min |
| NWS Greenville-Spartanburg, SC: severe thunderstorm warnings | 425 | 241 | 43% | 475 | 76% | 26 min |
| NWS Blacksburg, VA: severe thunderstorm warnings | 449 | 253 | 44% | 528 | 78% | 23 min |
| NWS Newport/Morehead City, NC: severe thunderstorm warnings | 197 | 54 | 73% | 104 | 74% | 26 min |
| NWS Raleigh, NC: severe thunderstorm warnings | 469 | 256 | 45% | 483 | 87% | 23 min |
| NWS Wakefield, VA: severe thunderstorm warnings | 288 | 138 | 52% | 333 | 73% | 22 min |
| NWS Wilmington, NC: severe thunderstorm warnings | 176 | 83 | 53% | 176 | 78% | 20 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
1,204 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 county
Every county with at least one alert. A county page lists each alert that covered it.
- Wake County60
- Johnston County59
- Sampson County54
- Craven County52
- Harnett County48
- Randolph County44
- Duplin County42
- Rockingham County42
- Durham County42
- Iredell County42
- Columbus County42
- Mecklenburg County39
- Surry County39
- Chatham County39
- Stokes County38
- Montgomery County37
- Richmond County37
- Bladen County37
- Robeson County37
- Cumberland County36
- Jones County36
- Guilford County36
- Catawba County36
- Lincoln County36
- Onslow County35
- Beaufort County35
- Rowan County34
- Moore County34
- Alamance County33
- Davidson County33
- Franklin County33
- Granville County32
- Lee County32
- Orange County31
- Halifax County31
- Anson County30
- Rutherford County29
- Wilkes County29
- Pitt County29
- Wayne County28
60 more counties
- Caswell County28
- Nash County28
- Gaston County27
- Cabarrus County27
- Lenoir County26
- Pamlico County26
- Cleveland County25
- Henderson County24
- Scotland County24
- Hoke County23
- Edgecombe County23
- Burke County22
- Union County22
- Stanly County22
- Vance County22
- Wilson County22
- Person County21
- Polk County21
- Brunswick County20
- Hyde County20
- Northampton County20
- McDowell County19
- Warren County19
- Pender County19
- Carteret County19
- Dare County19
- Cherokee County18
- Bertie County18
- Alexander County18
- Yadkin County18
- Forsyth County18
- Martin County18
- Buncombe County17
- Hertford County17
- Alleghany County17
- Ashe County17
- Caldwell County16
- Tyrrell County15
- Washington County14
- Gates County14
- Currituck County14
- Greene County14
- Davie County13
- Transylvania County13
- Haywood County12
- Swain County12
- Camden County12
- Mitchell County12
- Graham County11
- Madison County11
- Yancey County11
- Pasquotank County10
- Clay County10
- Avery County10
- Jackson County9
- Chowan County9
- New Hanover County9
- Perquimans County8
- Watauga County8
- Macon County7
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20072009
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.