[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 231306
SWOMCD
SPC MCD 231306 
TXZ000-231430-

MESOSCALE DISCUSSION 2428
NWS STORM PREDICTION CENTER NORMAN OK
0706 AM CST TUE NOV 23 2004

AREAS AFFECTED...PORTIONS OF CENTRAL AND SERN TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 231306Z - 231430Z

WW MAY BE NEEDED BY MID-LATE MORNING ACROSS PORTIONS OF CENTRAL TX.

THUNDERSTORMS EXPECTED TO INCREASE IN AREAL COVERAGE THROUGH 15Z
ACROSS PORTIONS OF CENTRAL INTO SERN TX.  INITIAL THREAT WILL BE
LARGE HAIL WITH AN INCREASING TORNADO POTENTIAL AFTER 16Z.

WV IMAGERY INDICATED A COUPLE OF SHORT WAVE TROUGHS DOWNSTREAM OF
THE MAIN UPPER LOW WHICH IS CURRENTLY LOCATED OVER SERN AZ/SWRN NM/
NRN MEXICO.  LARGE SCALE FORCING ASSOCIATED WITH A SHORT WAVE TROUGH
MOVING INTO WRN OK AND A SECOND ONE ALONG THE MID/UPPER TX COAST IS
AIDING IN ONGOING CONVECTION OVER NWRN TX AND CENTRAL TX TO JUST OFF
THE UPPER TX COAST.  INCREASING DIFFLUENT FLOW ALOFT AHEAD OF THE
MAIN UPPER LOW AND AN INCREASING BROAD SLY LLJ OVER CENTRAL/ERN TX
WILL SUPPORT ADDITIONAL CONVECTIVE DEVELOPMENT THROUGH THE MORNING. 


SELY SURFACE WINDS AND SLY LLJ WILL CONTINUE TO MOISTEN THE BOUNDARY
LAYER AND COMBINED WITH STEEP LAPSE RATES /8.4 C/KM PER 12Z CRP
SOUNDING/ ALREADY IN PLACE WILL RESULT IN SUFFICIENT INSTABILITY FOR
LARGE HAIL.  THE ONSET OF SURFACE HEATING AND INCREASING ASCENT IS
EXPECTED TO WEAKEN THE LOW-LEVEL CAP EVIDENT AT 12Z CRP SOUNDING FOR
SURFACE BASED STORMS TO DEVELOP BY MID MORNING.  AT THAT TIME...
TORNADO POTENTIAL WILL INCREASE GIVEN SUFFICIENT LOW-LEVEL
DIRECTIONAL SHEAR/CURVED HODOGRAPHS PER 09Z RUC FORECAST SOUNDINGS
SHOWING 0-1 KM SRH AR0UND 200 M2/S2.

..PETERS.. 11/23/2004

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

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

32329601 32399480 31699417 30569400 29729402 29029545
29249665 29699784 30089870 31169830 32079709 

WWWW