Weather alerts in Tennessee, 2010
2,218 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
- 2,218
- Warnings
- 1,341
- Watches
- 127
- Advisories
- 462
- Busiest month
- May615 alerts
- Busiest day
- May 1, 2010144 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
29 of 158 tornado warnings covering Tennessee in 2010 had a tornado report inside them; 31 of 42 tornado reports fell inside a warning, on average 17 minutes after it went out.
Tennessee, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 158 | 29 | 82% | 42 | 74% | 17 min |
| Severe thunderstorm warnings | 802 | 380 | 53% | 670 | 72% | 20 min |
| Flash flood warnings | 225 | 96 | 57% | 211 | 87% | 170 min |
Each office's whole area, 2010
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Nashville, TN: tornado warnings | 65 | 11 | 83% | 16 | 63% | 13 min |
| NWS Nashville, TN: severe thunderstorm warnings | 375 | 124 | 67% | 240 | 65% | 16 min |
| NWS Nashville, TN: flash flood warnings | 44 | 13 | 70% | 31 | 58% | 115 min |
| NWS Huntsville, AL: tornado warnings | 67 | 18 | 73% | 30 | 73% | 20 min |
| NWS Huntsville, AL: severe thunderstorm warnings | 197 | 79 | 60% | 238 | 49% | 19 min |
| NWS Huntsville, AL: flash flood warnings | 59 | 28 | 53% | 75 | 87% | 95 min |
| NWS Memphis, TN: tornado warnings | 109 | 28 | 74% | 51 | 86% | 18 min |
| NWS Memphis, TN: severe thunderstorm warnings | 436 | 188 | 57% | 371 | 73% | 22 min |
| NWS Memphis, TN: flash flood warnings | 283 | 118 | 58% | 247 | 93% | 150 min |
| NWS Atlanta, GA: tornado warnings | 37 | 3 | 92% | 11 | 27% | 14 min |
| NWS Atlanta, GA: severe thunderstorm warnings | 357 | 181 | 49% | 495 | 59% | 17 min |
| NWS Atlanta, GA: flash flood warnings | 22 | 9 | 59% | 21 | 86% | 75 min |
| NWS Morristown, TN: tornado warnings | 30 | 6 | 80% | 9 | 89% | 20 min |
| NWS Morristown, TN: severe thunderstorm warnings | 212 | 158 | 25% | 289 | 79% | 22 min |
| NWS Morristown, TN: flash flood warnings | 23 | 12 | 48% | 23 | 78% | 67 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
2,218 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.
- Shelby County268
- Tipton County252
- Lauderdale County249
- Fayette County249
- Haywood County241
- Henderson County234
- Hardin County232
- Madison County231
- Dyer County230
- Decatur County227
- Gibson County227
- Chester County226
- Hardeman County224
- McNairy County222
- Carroll County216
- Crockett County210
- Lake County202
- Obion County199
- Davidson County193
- Weakley County192
- Henry County190
- Blount County187
- Franklin County185
- Williamson County184
- Hickman County183
- Lincoln County174
- Perry County172
- Dickson County167
- Sevier County165
- Humphreys County163
- Maury County163
- Wilson County161
- Cocke County160
- Greene County160
- Rutherford County160
- Monroe County160
- Montgomery County158
- Lewis County157
- Benton County154
- Cheatham County154
55 more counties
- Lawrence County154
- Carter County151
- Moore County151
- Wayne County148
- Johnson County146
- Hamilton County146
- Sumner County145
- Unicoi County144
- Robertson County144
- Giles County143
- Smith County143
- Stewart County142
- Houston County140
- Jackson County140
- Marshall County136
- Polk County134
- Morgan County132
- Bedford County132
- Macon County132
- Overton County131
- McMinn County131
- Marion County131
- Clay County130
- Putnam County129
- Trousdale County128
- DeKalb County127
- Bledsoe County125
- Meigs County125
- Hancock County124
- Sullivan County123
- Scott County123
- White County123
- Knox County123
- Rhea County123
- Sequatchie County123
- Bradley County122
- Claiborne County121
- Washington County120
- Campbell County119
- Cumberland County118
- Pickett County118
- Anderson County117
- Hawkins County116
- Cannon County116
- Fentress County116
- Warren County116
- Coffee County115
- Roane County115
- Loudon County113
- Union County113
- Grainger County105
- Grundy County102
- Van Buren County102
- Jefferson County96
- Hamblen County89
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.