Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 753

May 7, 201246 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 7, 2012, 7:54 PM CDT for 46 counties in Texas. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued
May 7, 2012, 7:54 PM CDT (00:54 UTC)
Expired
May 7, 2012, 9:00 PM CDT
In force
66 min
Issued by
the Storm Prediction Center
All 46 counties

Atascosa County, TX, Bandera County, TX, Bastrop County, TX, Bee County, TX, Bexar County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Comal County, TX, DeWitt County, TX, Dimmit County, TX, Duval County, TX, Ellis County, TX, Falls County, TX, Fayette County, TX, Freestone County, TX, Frio County, TX, Goliad County, TX, Gonzales County, TX, Guadalupe County, TX, Hays County, TX, Henderson County, TX, Jim Wells County, TX, Karnes County, TX, Kaufman County, TX, Kinney County, TX, La Salle County, TX, Lee County, TX, Leon County, TX, Limestone County, TX, Live Oak County, TX, Maverick County, TX, McLennan County, TX, McMullen County, TX, Medina County, TX, Milam County, TX, Navarro County, TX, Rains County, TX, Robertson County, TX, Travis County, TX, Uvalde County, TX, Van Zandt County, TX, Webb County, TX, Williamson County, TX, Wilson County, TX, Zavala County, TX

The radar

The Austin/San Antonio radar (KEWX), 39 km from the middle of the area, began a volume at 00:54 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 nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 0.9 hours before the alert went out and 267 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.

Skew-T log-pSkew-T log-p diagram, Corpus Christi, TX at 00:00Z on 2012-05-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1286 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Corpus Christi, TX at 00:00Z on 2012-05-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -57 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1286 J/kg
Mixed-layer CIN
-248 J/kg
Mixed-layer LCL
1023 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-57 m²/s²
0-3 km storm-relative helicity
-30 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

482 
ACUS11 KWNS 080055
SWOMCD
SPC MCD 080054
TXZ000-080200-

MESOSCALE DISCUSSION 0753
NWS STORM PREDICTION CENTER NORMAN OK
0754 PM CDT MON MAY 07 2012

AREAS AFFECTED...NERN TO S TX

CONCERNING...SEVERE THUNDERSTORM WATCH 263...

VALID 080054Z - 080200Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 263
CONTINUES.

SUMMARY...REMNANT TSTM CLUSTERS INVOF TX HILL COUNTRY HAVE BECOME
INCREASINGLY DISORGANIZED...WITH PULSE STORMS ALONG THE COLD FRONT
IN NERN TX. RISKS FOR ISOLATED SEVERE HAIL AND LOCALLY DAMAGING
WINDS MAY PERSIST FOR THE NEXT COUPLE OF HOURS BUT WILL LIKELY
DIMINISH WITH TIME THIS EVENING.

DISCUSSION...MCS OVER THE TX HILL COUNTRY HAS APPEARED INCREASINGLY
DISORGANIZED IN THE PAST HOUR WITH OUTFLOW SURGING AHEAD OF STRONGER
CORES APPROACHING THE AUSTIN/SAN ANTONIO AREA. WITH THE ONSET OF
NOCTURNAL COOLING...MODIFIED 00Z CRP RAOB WOULD SUGGEST THAT
STRENGTHENING MLCIN MAY CURTAIL MCS REINTENSIFICATION WITHIN A
WEAKLY SHEARED ENVIRONMENT. STILL...WITH RENEWED UPDRAFTS WITH SRN
EXTENT ALONG THE RIO GRANDE WITHIN A HOT ENVIRONMENT /100 F AT 00Z
AT LRD/...A SMALL WW MAY BE POSSIBLE FOR PARTS OF S TX.

FARTHER NE...PULSE UPDRAFTS WITH MINIMAL DEEP-LAYER SHEAR /PER 00Z
FWD RAOB/ ALONG THE COLD FRONT INTO NERN TX SHOULD POSE A NEAR-TERM
RISK FOR SEVERE HAIL AND LOCALIZED MICROBURSTS.

..GRAMS.. 05/08/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...HGX...FWD...CRP...EWX...BRO...

LAT...LON   29320090 29730036 29779871 30649766 32489675 32969596
            32859571 32239568 31709569 30979607 28999718 27399806
            27039890 27139940 28360054 29320090

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 7, 7:39 PM CDTSevere Thunderstorm WatchSPCCamp, Gregg, Harrison, Marion, Morris, Panola and 5 more4 hr
May 7, 9:15 PM CDTMesoscale DiscussionSPCCamp, Cass, Gregg, Harrison, Marion, Morris and 6 more60 min
May 7, 9:46 PM CDTMesoscale DiscussionSPCAndrews, Borden, Crane, Crockett, Dawson, Ector and 15 more89 min
May 8, 1:42 AM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bexar, Comal, Dimmit, Edwards and 13 more93 min
May 8, 10:44 AM CDTMesoscale DiscussionSPCBee, Brooks, Duval, Frio, Goliad, Jim Hogg and 11 more61 min
May 8, 10:58 AM CDTSevere Thunderstorm WatchSPCAransas, Atascosa, Bee, Brooks, Calhoun, Cameron and 28 more8 hr
May 8, 1:37 PM CDTMesoscale DiscussionSPCBrewster, Culberson, El Paso, Hudspeth, Jeff Davis, Presidio and 1 more113 min
May 8, 2:07 PM CDTSevere Thunderstorm WatchSPCBrewster, Culberson, El Paso, Hudspeth, Jeff Davis, Presidio7 hr
May 8, 3:03 PM CDTMesoscale DiscussionSPCCameron, Hidalgo, Starr, Willacy87 min
May 8, 4:53 PM CDTMesoscale DiscussionSPCBrewster, Culberson, El Paso, Hudspeth, Jeff Davis, Presidio67 min
May 8, 5:47 PM CDTMesoscale DiscussionSPCCameron, Hidalgo, Kenedy, Willacy58 min

Nearby

Mesoscale Discussions in Texas, 2012Every mesoscale discussion 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.