Alert archive / Oklahoma / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 12
The Storm Prediction Center issued this severe thunderstorm watch at Feb 24, 2011, 4:10 AM CST for 23 counties in Oklahoma; 22 counties in Texas. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 24, 2011, 4:10 AM CST (10:10 UTC)
- Expired
- Feb 24, 2011, 11:00 AM CST
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 45 counties
Beckham County, OK, Caddo County, OK, Canadian County, OK, Carter County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, Lincoln County, OK, Love County, OK, McClain County, OK, Murray County, OK, Oklahoma County, OK, Pottawatomie County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Archer County, TX, Baylor County, TX, Borden County, TX, Childress County, TX, Clay County, TX, Cottle County, TX, Dickens County, TX, Foard County, TX, Garza County, TX, Hardeman County, TX, Haskell County, TX, Howard County, TX, Kent County, TX, King County, TX, Knox County, TX, Mitchell County, TX, Motley County, TX, Scurry County, TX, Stonewall County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX
The radar
The Altus AFB radar (KFDR), 70 km from the middle of the area, began a volume at 10:13 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 24, 5:42 AM CST | Severe Thunderstorm Warning | OUN | Jackson, Tillman | 48 min |
| Feb 24, 9:11 AM CST | Severe Thunderstorm Warning | OUN | Carter, Jefferson, Love | 49 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Norman, OK (KOUN), launched 00:00Z, 10.2 hours before the alert went out and 242 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 337 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 919 m above ground
- 0-6 km bulk shear
- 79 kt
- 0-1 km storm-relative helicity
- 120 m²/s²
- 0-3 km storm-relative helicity
- 87 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 23, 8:43 PM CST | Mesoscale Discussion | SPC | Craig, Nowata, Osage, Ottawa, Pawnee, Rogers and 1 more | 62 min |
| Feb 24, 3:07 AM CST | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Custer and 17 more | 113 min |
| Feb 24, 7:47 AM CST | Mesoscale Discussion | SPC | Cleveland, Cotton, Garvin, Grady, Jefferson, McClain and 3 more | 118 min |
| Feb 24, 10:34 AM CST | Mesoscale Discussion | SPC | Choctaw, Haskell, Latimer, LeFlore, McCurtain, Pushmataha | 56 min |
| Feb 24, 11:25 AM CST | Tornado Watch | SPC | Adair, Choctaw, Haskell, Latimer, LeFlore, McCurtain and 3 more | 9 hr |
| Feb 24, 2:39 PM CST | Mesoscale Discussion | SPC | Haskell, Latimer, LeFlore, McCurtain, Muskogee, Sequoyah | 66 min |
| Feb 24, 5:26 PM CST | Mesoscale Discussion | SPC | Cass, Harrison, Marion, Panola, Rusk, Shelby | 94 min |
Nearby
Severe Thunderstorm Watches in Oklahoma, 2011Severe Thunderstorm Watches in Texas, 2011Every severe thunderstorm watch in 2011
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.