Alert archive / Texas / Mesoscale Discussions in 2003

Mesoscale Discussion 795

May 6, 200317 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 6, 2003, 2:21 PM CDT for 17 counties in Texas. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued: May 6, 2003, 2:21 PM CDT (19:21 UTC)
Expired: May 6, 2003, 4:15 PM CDT
In force: 114 min
Issued by: the Storm Prediction Center

Counties Austin County, TX, Bastrop County, TX, Brazos County, TX, Burleson County, TX, Colorado County, TX, Fayette County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Lee County, TX, Madison County, TX, Milam County, TX, Montgomery County, TX, Robertson County, TX, Walker County, TX, Waller County, TX, Washington County, TX

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 7.4 hours before the alert went out and 293 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

117 
ACUS11 KWNS 061922
SWOMCD
SPC MCD 061921 
TXZ000-062115-

MESOSCALE DISCUSSION 0795
NWS STORM PREDICTION CENTER NORMAN OK
0221 PM CDT TUE MAY 06 2003

AREAS AFFECTED...ECNTRL TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 061921Z - 062115Z

CONVECTION E OF AUSTIN TX SHOULD CONTINUE TO STRENGTHEN SLOWLY AS IT
MOVES EWD. ISOLATED LARGE HAIL AND/OR DAMAGING WINDS WILL BE
POSSIBLE WITH THE CONVECTION. WW MAY BE NECESSARY ACROSS PORTIONS OF
CNTRL AND ERN TX BY 2030Z.

DEWPOINTS IN THE LOWER TO MID 70S F AND SFC TEMPS IN THE MID TO
UPPER 80S WERE CONTRIBUTING TO MLCAPE AROUND 3000 J/KG. THE AXIS OF
VERY UNSTABLE AIR WAS ELONGATED FROM FAR S TX NEWD INTO SE TX. AS
THE CONVECTION MOVES EWD INTO THE INSTABILITY AXIS...IT SHOULD
INCREASE IN INTENSITY. DEEP LAYER SHEAR OF 40 KT WAS MARGINALLY
SUFFICIENT FOR SUPERCELLS. HOWEVER...DEGREE OF INSTABILITY MAY BE
ENOUGH FOR A FEW SUPERCELLS WITH LARGE HAIL AND OR/DAMAGING WIND
GUSTS. WW MAY BE REQUIRED IN THE NEXT HOUR IF ACTIVITY CONTINUES  TO
DEVELOP ENEWD. 


..BROYLES.. 05/06/2003

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

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

30229741 31049703 31239614 31359523 30019520 29709555
29549629 29439740

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 6, 8:44 AM CDT	Mesoscale Discussion	SPC	Bastrop, Bell, Blanco, Brazos, Burleson, Burnet and 14 more	2 hr
May 6, 9:10 AM CDT	Severe Thunderstorm Watch	SPC	Bell, Bosque, Brown, Burnet, Callahan, Coleman and 28 more	6 hr
May 6, 12:14 PM CDT	Mesoscale Discussion	SPC	Bandera, Bell, Bexar, Blanco, Burnet, Comal and 16 more	2 hr
May 6, 2:47 PM CDT	Mesoscale Discussion	SPC	Collin, Dallas, Delta, Fannin, Franklin, Grayson and 10 more	118 min
May 6, 4:46 PM CDT	Mesoscale Discussion	SPC	Collin, Dallas, Delta, Denton, Ellis, Fannin and 7 more	119 min
May 6, 5:15 PM CDT	Severe Thunderstorm Watch	SPC	Collin, Cooke, Dallas, Delta, Denton, Eastland and 19 more	5 hr

Nearby

Mesoscale Discussions in Texas, 2003 Every 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.