Alert archive / Texas / Mesoscale Discussions in 2009
Mesoscale Discussion 804
The Storm Prediction Center issued this mesoscale discussion at May 12, 2009, 3:43 PM CDT for 45 counties in Texas. It was in force for 62 min.
The area
The outline as issued.
The facts
- Issued
- May 12, 2009, 3:43 PM CDT (20:43 UTC)
- Expired
- May 12, 2009, 4:45 PM CDT
- In force
- 62 min
- Issued by
- the Storm Prediction Center
All 45 counties
Andrews County, TX, Armstrong County, TX, Bailey County, TX, Borden County, TX, Briscoe County, TX, Castro County, TX, Childress County, TX, Cochran County, TX, Cottle County, TX, Crane County, TX, Crosby County, TX, Dawson County, TX, Dickens County, TX, Donley County, TX, Ector County, TX, Fisher County, TX, Floyd County, TX, Gaines County, TX, Garza County, TX, Glasscock County, TX, Hale County, TX, Hall County, TX, Hockley County, TX, Howard County, TX, Irion County, TX, Kent County, TX, King County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Martin County, TX, Midland County, TX, Mitchell County, TX, Motley County, TX, Parmer County, TX, Pecos County, TX, Randall County, TX, Reagan County, TX, Scurry County, TX, Sterling County, TX, Stonewall County, TX, Swisher County, TX, Terrell County, TX, Terry County, TX, Upton County, TX
The radar
The Lubbock radar (KLBB), 69 km from the middle of the area, began a volume at 20:45 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Midland Regional, TX (KMAF), launched 12:00Z, 8.7 hours before the alert went out and 125 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
- 2687 J/kg
- Mixed-layer CIN
- -151 J/kg
- Mixed-layer LCL
- 685 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 141 m²/s²
- 0-3 km storm-relative helicity
- 173 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 12, 5:41 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Borden, Briscoe, Childress, Coke, Collingsworth and 24 more | 5 hr |
Nearby
Mesoscale Discussions in Texas, 2009Every mesoscale discussion in 2009
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.