Alert archive / Texas / Mesoscale Discussions in 2004

Mesoscale Discussion 682

May 13, 200433 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 13, 2004, 3:52 AM CDT for 33 counties in Texas. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
May 13, 2004, 3:52 AM CDT (08:52 UTC)
Expired
May 13, 2004, 5:15 AM CDT
In force
83 min
Issued by
the Storm Prediction Center
All 33 counties

Anderson County, TX, Angelina County, TX, Austin County, TX, Bastrop County, TX, Brazos County, TX, Burleson County, TX, Chambers County, TX, Cherokee County, TX, Fayette County, TX, Freestone County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Henderson County, TX, Houston County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Limestone County, TX, Madison County, TX, Milam County, TX, Montgomery County, TX, Nacogdoches County, TX, Polk County, TX, Robertson County, TX, Rusk County, TX, San Jacinto County, TX, Shelby County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Waller County, TX, Washington County, TX

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 8.9 hours before the alert went out and 263 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, Fort Worth, TX at 00:00Z on 2004-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3034 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, Fort Worth, TX at 00:00Z on 2004-05-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 square meters per square second.193958Sfc1 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
3034 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
1247 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.5

Open this sounding in Storm Lab

The text

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

530 
ACUS11 KWNS 130853
SWOMCD
SPC MCD 130852 
TXZ000-131015-

MESOSCALE DISCUSSION 0682
NWS STORM PREDICTION CENTER NORMAN OK
0352 AM CDT THU MAY 13 2004

AREAS AFFECTED...SERN/ERN TX

CONCERNING...CONVECTIVE TRENDS 

VALID 130852Z - 131015Z

...THUNDERSTORMS SHOULD CONTINUE TO DEVELOP AND SPREAD NWD ACROSS
PORTIONS OF ERN TX...

LLJ/WARM ADVECTION APPEARS TO BE INCREASING FROM THE NWRN GULF OF
MEXICO INTO ECNTRL TX AHEAD OF WEAK UPPER SHORTWAVE TROUGH
APPROACHING FROM SWRN TX.  THIS INCREASE IN WARM ADVECTION IS AIDING
THE GRADUAL EXPANSION OF CONVECTION OVER SERN TX.  ALTHOUGH DEEP
LAYER VERTICAL SHEAR IS MARGINAL...LOW LEVEL SHEAR MAY PROVE STRONG
ENOUGH TO SUPPORT WEAK STORM ROTATION WITHIN MARITIME TROPICAL
ENVIRONMENT.  THIS IS OF SOME CONCERN IF DISCRETE STRUCTURES WERE TO
EVOLVE WITHIN THE LARGER PRECIPITATION SHIELD. CURRENT THINKING IS
SHOWERS/TSTMS WILL SLOWLY EXPAND AND INCREASE IN DEPTH WITH THE
LIKLIHOOD FOR MULTIPLE CONVECTIVE CLUSTERS SPREADING ACROSS ERN TX
AS THE MORNING PROGRESSES.

..DARROW.. 05/13/2004

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

ATTN...WFO...LCH...SHV...HGX...FWD...EWX...

29749750 32579612 32099407 29659451

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 12, 8:04 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Fisher, Foard, Hardeman and 13 more86 min
May 13, 8:30 AM CDTTornado WatchSPCAngelina, Austin, Bastrop, Brazos, Burleson, Caldwell and 17 more6 hr
May 13, 9:54 AM CDTMesoscale DiscussionSPCAngelina, Austin, Bastrop, Brazos, Burleson, Caldwell and 17 more96 min
May 13, 10:20 AM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Cottle, Dickens, Foard and 10 more115 min
May 13, 10:45 AM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Clay, Foard, Hardeman, Knox and 2 more6 hr
May 13, 12:10 PM CDTTornado WatchSPCAngelina, Austin, Brazoria, Chambers, Colorado, Fayette and 22 more6 hr
May 13, 12:26 PM CDTMesoscale DiscussionSPCBandera, Brown, Callahan, Coke, Coleman, Concho and 26 more2 hr
May 13, 12:48 PM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Foard, Haskell, Knox and 4 more117 min
May 13, 12:55 PM CDTTornado WatchSPCBrown, Callahan, Coleman, Concho, Eastland, Haskell and 14 more6 hr
May 13, 1:38 PM CDTMesoscale DiscussionSPCAustin, Brazoria, Chambers, Colorado, Fayette, Fort Bend and 15 more97 min
May 13, 2:30 PM CDTTornado WatchSPCAtascosa, Bandera, Bastrop, Bexar, Caldwell, Comal and 21 more6 hr
May 13, 2:48 PM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Haskell, Wichita87 min
May 13, 2:57 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Concho, Eastland, Haskell and 14 more2 hr
May 13, 3:34 PM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bastrop, Bexar, Caldwell, Comal and 21 more86 min
May 13, 5:22 PM CDTMesoscale DiscussionSPCAngelina, Austin, Brazoria, Chambers, Colorado, Fort Bend and 17 more53 min
May 13, 5:54 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Concho, Eastland, Haskell and 14 more96 min
May 13, 6:55 PM CDTSevere Thunderstorm WatchSPCBandera, Edwards, Gillespie, Kerr, Kimble, Mason and 6 more5 hr

Nearby

Mesoscale Discussions in Texas, 2004Every mesoscale discussion in 2004

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.