Alert archive / Texas / Mesoscale Discussions in 2011
Mesoscale Discussion 752
The Storm Prediction Center issued this mesoscale discussion at May 12, 2011, 2:57 AM CDT for 31 counties in Texas. It was in force for 33 min.
The area
The outline as issued.
The facts
- Issued
- May 12, 2011, 2:57 AM CDT (07:57 UTC)
- Expired
- May 12, 2011, 3:30 AM CDT
- In force
- 33 min
- Issued by
- the Storm Prediction Center
All 31 counties
Atascosa County, TX, Bandera County, TX, Bastrop County, TX, Bexar County, TX, Blanco County, TX, Caldwell County, TX, Comal County, TX, Dimmit County, TX, Edwards County, TX, Frio County, TX, Gillespie County, TX, Guadalupe County, TX, Hays County, TX, Kendall County, TX, Kerr County, TX, Kimble County, TX, Kinney County, TX, La Salle County, TX, Llano County, TX, Mason County, TX, Maverick County, TX, Medina County, TX, Menard County, TX, Real County, TX, Schleicher County, TX, Sutton County, TX, Travis County, TX, Uvalde County, TX, Val Verde County, TX, Wilson County, TX, Zavala County, TX
The radar
The Laughlin AFB radar (KDFX), 49 km from the middle of the area, began a volume at 08:01 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
Del Rio, TX (KDRT), launched 00:00Z, 8.0 hours before the alert went out and 98 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
- 2151 J/kg
- Mixed-layer CIN
- -7 J/kg
- Mixed-layer LCL
- 2314 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- -3 m²/s²
- 0-3 km storm-relative helicity
- 32 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.9
The text
As transmitted, in the capitals the NWS used until 2016.
905
ACUS11 KWNS 120758
SWOMCD
SPC MCD 120757
TXZ000-120830-
MESOSCALE DISCUSSION 0752
NWS STORM PREDICTION CENTER NORMAN OK
0257 AM CDT THU MAY 12 2011
AREAS AFFECTED...TX BIG BEND EWD TO SOUTH CENTRAL TX
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 120757Z - 120830Z
WW WILL LIKELY BE NEEDED EARLY THIS MORNING FROM THE TX BIG BEND EWD
INTO SOUTH CENTRAL TX WHERE TSTMS ARE EXPECTED TO DEVELOP AND EXPAND
IN COVERAGE DURING THE NEXT FEW HOURS. LARGE HAIL AND DAMAGING
WINDS WILL BE THE PRIMARY THREATS.
EARLY MORNING SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE
LOCATED JUST W OF DRT IN NRN MEXICO...WITH THE PRIMARY BAROCLINIC
ZONE EXTENDING ENEWD THROUGH SOUTH CENTRAL TX /JUST N OF BAZ/ AND
THEN INTO SERN TX AND CENTRAL LA /ALONG AND S OF ONGOING STORMS IN
THAT REGION/. A WIND SHIFT EXTENDED SEWD FROM THE LOW TO THE TX
COASTAL PLAIN BETWEEN CRP AND VCT. THE AIR MASS ACROSS CENTRAL AND
SRN TX IS STRONGLY UNSTABLE /MUCAPE 2000-4000 J PER KG/ AND
SUFFICIENT EFFECTIVE BULK SHEAR /35-50 KT/ TO SUPPORT ORGANIZED
STORMS.
WATER VAPOR IMAGERY SHOWED A MIDLEVEL JET STREAK ADVANCING EWD
ACROSS THE PERMIAN BASIN...WHILE IR AND RADAR IMAGERY INDICATED CU
DEVELOPING ALONG THE PRIMARY BAROCLINIC ZONE TO THE N THROUGH NW OF
DRT AND S OF SANDERSON TX NEAR THE INTERNATIONAL BORDER. THIS IS
LIKELY BEING SUPPORTED BY DCVA GLANCING THIS REGION FROM THE PERMIAN
BASIN IMPULSE/JETLET. GIVEN THE EARLY SIGNS OF UPDRAFTS AND
AGREEMENT FOR ADDITIONAL DEVELOPMENT PER 05Z EXPERIMENTAL WRF-HRRR
AND 00Z ECMWF...A WW WILL BE COORDINATED WITH THE AFFECTED WFOS
EARLY THIS MORNING.
..PETERS.. 05/12/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CRP...EWX...SJT...MAF...
LAT...LON 29880177 30230168 30970041 30759789 30229722 29069782
28439875 28199926 28200012 28820057 29180076 29880177SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 7:43 PM CDT | Mesoscale Discussion | SPC | Anderson, Bell, Blanco, Bowie, Burnet, Camp and 20 more | 62 min |
| May 11, 11:25 PM CDT | Mesoscale Discussion | SPC | Austin, Bandera, Bastrop, Bexar, Brazos, Burleson and 27 more | 65 min |
| May 12, 3:18 AM CDT | Severe Thunderstorm Watch | SPC | Bandera, Dimmit, Edwards, Frio, Kerr, Kinney and 7 more | 5 hr |
| May 12, 7:27 AM CDT | Mesoscale Discussion | SPC | Atascosa, Bandera, Bee, Bexar, Brooks, Dimmit and 26 more | 33 min |
| May 12, 7:52 AM CDT | Severe Thunderstorm Watch | SPC | Aransas, Atascosa, Bandera, Bee, Bexar, Brooks and 33 more | 9 hr |
| May 12, 8:46 AM CDT | Mesoscale Discussion | SPC | Bastrop, Bell, Bosque, Brazos, Burleson, Caldwell and 22 more | 59 min |
| May 12, 9:02 AM CDT | Severe Thunderstorm Watch | SPC | Anderson, Austin, Bastrop, Bell, Blanco, Bosque and 53 more | 6 hr |
| May 12, 11:43 AM CDT | Mesoscale Discussion | SPC | Anderson, Aransas, Austin, Bee, Brazos, Burleson and 33 more | 92 min |
| May 12, 1:46 PM CDT | Mesoscale Discussion | SPC | Fannin, Grayson, Lamar | 119 min |
| May 12, 3:17 PM CDT | Severe Thunderstorm Watch | SPC | Cooke, Fannin, Grayson, Lamar, Montague, Red River | 7 hr |
| May 12, 6:30 PM CDT | Mesoscale Discussion | SPC | Cooke, Fannin, Grayson, Lamar | 90 min |
Nearby
Mesoscale Discussions in Texas, 2011Every mesoscale discussion 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.