Alert archive / Texas / Mesoscale Discussions in 2011
Mesoscale Discussion 754
The Storm Prediction Center issued this mesoscale discussion at May 12, 2011, 8:46 AM CDT for 28 counties in Texas. It was in force for 59 min.
The area
The outline as issued.
The facts
- Issued
- May 12, 2011, 8:46 AM CDT (13:46 UTC)
- Expired
- May 12, 2011, 9:45 AM CDT
- In force
- 59 min
- Issued by
- the Storm Prediction Center
All 28 counties
Bastrop County, TX, Bell County, TX, Bosque County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Coryell County, TX, Dallas County, TX, Ellis County, TX, Falls County, TX, Fayette County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Johnson County, TX, Kaufman County, TX, Lavaca County, TX, Lee County, TX, Limestone County, TX, McLennan County, TX, Milam County, TX, Navarro County, TX, Robertson County, TX, Somervell County, TX, Tarrant County, TX, Travis County, TX, Washington County, TX, Williamson County, TX
The radar
The Ft Hood radar (KGRK), 44 km from the middle of the area, began a volume at 13:47 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
Fort Worth, TX (KFWD), launched 12:00Z, 1.8 hours before the alert went out and 191 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
- 1960 J/kg
- Mixed-layer CIN
- -69 J/kg
- Mixed-layer LCL
- 567 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 259 m²/s²
- 0-3 km storm-relative helicity
- 198 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 11.5
The text
As transmitted, in the capitals the NWS used until 2016.
321
ACUS11 KWNS 121346
SWOMCD
SPC MCD 121346
TXZ000-121445-
MESOSCALE DISCUSSION 0754
NWS STORM PREDICTION CENTER NORMAN OK
0846 AM CDT THU MAY 12 2011
AREAS AFFECTED...S-CNTRL THROUGH N-CNTRL TX
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 121346Z - 121445Z
STORMS MAY CONTINUE TO DEVELOP EWD AND NEWD THROUGH CNTRL AND
N-CNTRL TX. LARGE HAIL AND DAMAGING WIND WILL BE THE MAIN THREATS. A
WW MAY BE NEEDED SOON.
EARLY THIS MORNING STORMS CONTINUE TO INCREASE ALONG LEADING EDGE OF
MCS COLD POOL FROM JUST SW OF STEPHENVILLE SWD THROUGH S-CNTRL TX.
SOME UNCERTAINTY EXISTS REGARDING THE FUTURE EVOLUTION OF THE
ACTIVITY SINCE THE BOUNDARY LAYER HAS NOT RECOVERED. HOWEVER...THE
DOWNSTREAM ATMOSPHERE IS MODERATELY UNSTABLE WITH 2000 J/KG MUCAPE
AND STORMS MAY EVENTUALLY BECOME SURFACE BASED AS THE SURFACE LAYER
UNDERGOES SLOW BUT GRADUAL WARMING.
..DIAL.. 05/12/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...HGX...FWD...EWX...
LAT...LON 30049801 30829802 31609811 32129827 33019712 32589620
30569620 29289687 30049801SPC 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, 2:57 AM CDT | Mesoscale Discussion | SPC | Atascosa, Bandera, Bastrop, Bexar, Blanco, Caldwell and 25 more | 33 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, 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.