Alert archive / Texas / Mesoscale Discussions in 2003

Mesoscale Discussion 784

May 6, 200320 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 6, 2003, 8:44 AM CDT for 20 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 6, 2003, 8:44 AM CDT (13:44 UTC)
Expired
May 6, 2003, 10:45 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center

Counties Bastrop County, TX, Bell County, TX, Blanco County, TX, Brazos County, TX, Burleson County, TX, Burnet County, TX, Caldwell County, TX, Comal County, TX, Coryell County, TX, Falls County, TX, Freestone County, TX, Guadalupe County, TX, Hays County, TX, Lee County, TX, Limestone County, TX, McLennan County, TX, Milam County, TX, Robertson County, TX, Travis County, TX, Williamson County, TX

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, 1.7 hours before the alert went out and 259 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 12:00Z on 2003-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2816 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 12:00Z on 2003-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 167 square meters per square second.1939587897Sfc1 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
2816 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
1185 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
167 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.9
Supercell composite
6.2

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 061345
SWOMCD
SPC MCD 061344 
TXZ000-061545-

MESOSCALE DISCUSSION 0784
NWS STORM PREDICTION CENTER NORMAN OK
0844 AM CDT TUE MAY 06 2003

AREAS AFFECTED...CNTRL TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 061344Z - 061545Z

ELEVATED CONVECTION CURRENTLY IN CNTRL TEXAS SHOULD CONTINUE TO
INCREASE IN INTENSITY. LARGE HAIL WILL BE THE PRIMARY THREAT WITH
THE ACTIVITY. WW MAY BECOME NECESSARY WITHIN THE NEXT 1-2 HOURS.

VERY MOIST AIR MASS WAS IN PLACE ACROSS CNTRL TX WITH LOWER TO MID
70S. MLCAPE WERE 1500-2000 J/KG WITH 50 KT OF DEEP LAYER SHEAR. 12Z
DEL RIO SOUNDING SHOWED MOST OF THE INSTABILITY WAS ABOVE 800 MB. AS
A RESULT...THE CONVECTION WILL REMAIN ELEVATED. STEEP LAPSE RATES
AROUND 8.4 C/KM...STRONG ELEVATED INSTABILITY AND STRONG DEEP LAYER
SHEAR SHOULD RESULT IN A POTENTIAL FOR LARGE HAIL. 


..BROYLES.. 05/06/2003

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

ATTN...WFO...HGX...FWD...EWX...SJT...

29469851 30199866 30889854 31569757 32029642 31589603
30569607 29939701 29509792

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 9:10 AM CDTSevere Thunderstorm WatchSPCBell, Bosque, Brown, Burnet, Callahan, Coleman and 28 more6 hr
May 6, 12:14 PM CDTMesoscale DiscussionSPCBandera, Bell, Bexar, Blanco, Burnet, Comal and 16 more2 hr
May 6, 2:21 PM CDTMesoscale DiscussionSPCAustin, Bastrop, Brazos, Burleson, Colorado, Fayette and 11 more114 min
May 6, 2:47 PM CDTMesoscale DiscussionSPCCollin, Dallas, Delta, Fannin, Franklin, Grayson and 10 more118 min
May 6, 4:46 PM CDTMesoscale DiscussionSPCCollin, Dallas, Delta, Denton, Ellis, Fannin and 7 more119 min
May 6, 5:15 PM CDTSevere Thunderstorm WatchSPCCollin, Cooke, Dallas, Delta, Denton, Eastland and 19 more5 hr

Nearby

Mesoscale Discussions in Texas, 2003Every mesoscale discussion in 2003

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.