Alert archive / Texas / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 584
The Storm Prediction Center issued this severe thunderstorm watch at Aug 18, 2012, 2:05 PM CDT for Cotton County, Jefferson County, Tillman County, Oklahoma; 34 counties in Texas. It took effect at Aug 18, 2012, 2:10 PM CDT. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 18, 2012, 2:05 PM CDT (19:05 UTC)
- In effect from
- Aug 18, 2012, 2:10 PM CDT
- Expired
- Aug 18, 2012, 9:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 37 counties
Cotton County, OK, Jefferson County, OK, Tillman County, OK, Archer County, TX, Baylor County, TX, Briscoe County, TX, Castro County, TX, Childress County, TX, Clay County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Fisher County, TX, Floyd County, TX, Foard County, TX, Hale County, TX, Hall County, TX, Hardeman County, TX, Haskell County, TX, Jack County, TX, Jones County, TX, Kent County, TX, King County, TX, Knox County, TX, Montague County, TX, Motley County, TX, Palo Pinto County, TX, Parker County, TX, Shackelford County, TX, Stephens County, TX, Stonewall County, TX, Swisher County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Wise County, TX, Young County, TX
The radar
The Lubbock radar (KLBB), 135 km from the middle of the area, began a volume at 19:06 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- 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
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 4:36 PM CDT | Severe Thunderstorm Warning | FWD | Cooke, Denton, Wise | 54 min |
| Aug 18, 5:18 PM CDT | Severe Thunderstorm Warning | FWD | Jack, Palo Pinto, Young | 57 min |
| Aug 18, 5:58 PM CDT | Severe Thunderstorm Warning | FWD | Jack, Palo Pinto, Stephens, Young | 41 min |
| Aug 18, 5:59 PM CDT | Flash Flood Warning | FWD | Denton, Tarrant, Wise | 2 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Amarillo Airport, TX (KAMA), launched 12:00Z, 7.1 hours before the alert went out and 195 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
- 226 J/kg
- Mixed-layer CIN
- -197 J/kg
- Mixed-layer LCL
- 2149 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 6 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 3:52 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Beaver, Ellis, Harper, Woods, Woodward | 113 min |
| Aug 18, 9:29 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Blaine, Canadian, Custer, Dewey, Garfield and 5 more | 91 min |
| Aug 18, 1:10 PM CDT | Mesoscale Discussion | SPC | Cotton, Jackson, Tillman | 2 hr |
| Aug 18, 5:00 PM CDT | Mesoscale Discussion | SPC | Cotton, Jefferson, Tillman | 90 min |
| Aug 17, 7:53 PM CDT | Mesoscale Discussion | SPC | Bowie | 2 hr |
| Aug 18, 6:29 AM CDT | Mesoscale Discussion | SPC | Bowie | 2 hr |
Nearby
Severe Thunderstorm Watches in Texas, 2012Severe Thunderstorm Watches in Oklahoma, 2012Every severe thunderstorm watch in 2012
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.