Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 783

May 10, 201219 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 10, 2012, 11:36 PM CDT for 19 counties in Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
May 10, 2012, 11:36 PM CDT (04:36 UTC)
Expired
May 11, 2012, 1:00 AM CDT
In force
84 min
Issued by
the Storm Prediction Center

Counties Aransas County, TX, Brooks County, TX, Calhoun County, TX, Cameron County, TX, Hidalgo County, TX, Jackson County, TX, Jim Hogg County, TX, Jim Wells County, TX, Kenedy County, TX, Kleberg County, TX, Matagorda County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX, Starr County, TX, Victoria County, TX, Wharton County, TX, Willacy County, TX, Zapata County, TX

The radar

The Corpus Christi radar (KCRP), 36 km from the middle of the area, began a volume at 04:37 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, 4.6 hours before the alert went out and 39 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 2012-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2214 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 2012-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 204 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
2214 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
636 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
204 m²/s²
0-3 km storm-relative helicity
274 m²/s²
Significant tornado parameter
3.4
Supercell composite
14.5

Open this sounding in Storm Lab

The text

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

970 
ACUS11 KWNS 110437
SWOMCD
SPC MCD 110436
TXZ000-110600-

MESOSCALE DISCUSSION 0783
NWS STORM PREDICTION CENTER NORMAN OK
1136 PM CDT THU MAY 10 2012

AREAS AFFECTED...SOUTH TX...LOWER TO MIDDLE TX COAST

CONCERNING...TORNADO WATCH 273...

VALID 110436Z - 110600Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 273 CONTINUES.

SUMMARY...THE TORNADO THREAT MAY CONTINUE FOR ANOTHER HOUR OR TWO
ACROSS SOUTH TX. IN ADDITION...LARGE HAIL AND WIND DAMAGE MAY
ACCOMPANY THE MORE INTENSE THUNDERSTORMS. THE SEVERE THREAT MAY
DECREASE ACROSS PARTS OF THE MIDDLE TX COAST AS A CONVECTIVE LINE
MOVES NEWD TOWARDS WHARTON AND MATAGORDA COUNTIES OVER THE NEXT 1 TO
2 HOURS.

DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A WELL-DEFINED OUTFLOW
BOUNDARY FROM NEAR CORPUS CHRISTI EXTENDING SSWWD TO WEST OF RIO
GRANDE CITY IN FAR SOUTH TX. STRONG TO SEVERE THUNDERSTORMS ARE
ONGOING ALONG THE BOUNDARY WITH SFC DEWPOINTS AHEAD OF THE STORMS IN
THE MID 70S AND MESOANALYSIS SHOWING MODERATE INSTABILITY IN PLACE.
THIS ALONG WITH STRONG LARGE-SCALE ASCENT ASSOCIATED WITH AN
UPPER-LEVEL LOW OVER WEST TX WILL ALLOW THE THUNDERSTORM ACTIVITY TO
PERSIST INTO THE OVERNIGHT PERIOD. THE MOIST BOUNDARY LAYER...LOW
LCL HEIGHTS AND STRENGTHENING LOW-LEVEL SHEAR MAY RESULT IN A
CONTINUED TORNADO THREAT FOR ANOTHER HOUR OR TWO. THIS THREAT ALONG
WITH A POTENTIAL FOR LARGE HAIL AND WIND DAMAGE IS EXPECTED TO
DEVELOP SEWD INTO EXTREME SOUTH TX AFTER MIDNIGHT WHERE MLCAPE
VALUES ARE MAXIMIZED IN THE 2000 TO 3000 J/KG.

..BROYLES.. 05/11/2012

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

ATTN...WFO...HGX...CRP...BRO...

LAT...LON   27369906 27079940 26629929 26389895 26039776 25939725
            26229709 26699726 27109727 27579706 27979674 28339636
            28929533 29509592 29129675 28369759 27909796 27639850
            27369906

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 7:18 PM CDTMesoscale DiscussionSPCAransas, Atascosa, Austin, Bastrop, Bee, Bexar and 43 more57 min
May 10, 7:50 PM CDTTornado WatchSPCAransas, Atascosa, Austin, Bastrop, Bee, Bell and 48 more9 hr
May 10, 9:42 PM CDTMesoscale DiscussionSPCAransas, Atascosa, Austin, Bastrop, Bee, Bell and 36 more63 min
May 11, 1:40 AM CDTMesoscale DiscussionSPCAransas, Austin, Bee, Brazoria, Brooks, Calhoun and 25 more65 min
May 11, 2:41 AM CDTMesoscale DiscussionSPCCameron, Chambers, Galveston, Hidalgo, Jefferson, Kenedy and 3 more34 min
May 11, 1:22 PM CDTMesoscale DiscussionSPCAnderson, Bosque, Camp, Cherokee, Collin, Cooke and 28 more53 min
May 11, 2:13 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bandera, Bastrop, Bell, Bexar and 41 more2 hr
May 11, 5:18 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Austin, Bastrop, Bell, Blanco and 40 more87 min
May 11, 5:51 PM CDTMesoscale DiscussionSPCBee, Brooks, Duval, Goliad, Hidalgo, Jim Hogg and 7 more84 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.