[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 131852
SWOMCD
SPC MCD 131852 
TXZ000-OKZ000-132015-

MESOSCALE DISCUSSION 0858
NWS STORM PREDICTION CENTER NORMAN OK
0152 PM CDT FRI MAY 13 2005

AREAS AFFECTED...PORTIONS NW TX...ERN TX PANHANDLE...SWRN OK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 131852Z - 132015Z

TORNADO WW WILL BE ISSUED WITHIN AN HOUR.  TSTM DEVELOPMENT
ANTICIPATED BY 21Z FROM CDS AREA WWD TO INVOF CAPROCK. ACTIVITY
SHOULD EVOLVE RAPIDLY INTO SUPERCELL CHARACTER WITH VERY
LARGE/DESTRUCTIVE HAIL LIKELY. DAMAGING WIND AND TORNADO POTENTIAL
ALSO EXISTS...REINFORCED LOCALLY BY STORM-SCALE AND/OR MESOBETA
SCALE BOUNDARY INTERACTIONS.

SFC MESOANALYSIS -- INCLUDING W TX AND OK MESONET DATA -- INDICATES
PRONOUNCED MESOLOW CENTRAL/NERN FLOYD COUNTY AT 18Z.  ASSOCIATED
BOUNDARY LAYER CYCLONIC CIRCULATION ALSO IS EVIDENT IN CU PATHS ON
ANIMATED VIS IMAGERY.  DRYLINE EXTENDS DUE S THROUGH BORDEN COUNTY
AND IS EXPECTED TO MIX SLIGHTLY EWD TOWARD W EDGE OF DEEPER CU FIELD
-- NOW EVIDENT FROM SRN BRISCOE/MOTLEY COUNTIES SWD THROUGH COKE
COUNTY.  DIFFERENTIAL HEATING BOUNDARY -- ALONG EDGE OF SLOWLY
ERODING LOW CLOUD DECK -- CURVES FROM MAJOR COUNTY OK SWWD ACROSS
HARMON COUNTY...THEN OVER TX PANHANDLE THROUGH SRN DONLEY TO
OCHILTREE COUNTY TX.  OUTFLOW BOUNDARY FROM MORNING MCS IS BECOMING
MORE DIFFUSE AND LIFTING NWD THROUGH CDS AREA..SOON TO MERGE WITH
DIFFERENTIAL HEATING BOUNDARY.

BACKED LOW LEVEL FLOW AND ENLARGED HODOGRAPHS SHOULD REMAIN MOST
PRONOUNCED FROM JUST NE-E OF MESOLOW EWD INTO EXTREME SWRN
OK...COINCIDENT WITH SFC MOIST AXIS CONTAINING MID/UPPER 60S F DEW
POINTS.  THESE FACTORS COMBINE WITH DIABATICALLY DESTABILIZING
BOUNDARY LAYER AND STEEP MIDLEVEL LAPSE RATES -- EVIDENT IN 18Z AMA
RAOB AND RUC SOUNDINGS -- TO YIELD 2000-2500 J/KG MLCAPE AND RAPIDLY
WEAKENING CINH.  CONVERGENCE MAX W CDS INDICATES REGION FROM CDS
TOWARD PALO DURO CANYON SWD TO MESOLOW IS MOST FAVORED AREA FOR
SOONEST INITIATION...THOUGH OTHER DEVELOPMENT MAY OCCUR EWD OR NWD
ALONG OUTFLOW/HEATING BOUNDARIES INTO SW OK AND ERN TX PANHANDLE. 
DESPITE SOME MINOR WEAKNESSES EVIDENT IN LOW LEVEL FLOW...100-150
0-1 KM SRH AND 50 KT EFFECTIVE SHEAR AND FAVORABLY MOIST INFLOW
SUPPORT SUPERCELLS AND ENHANCED HAIL GENERATION.

..EDWARDS.. 05/13/2005

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

ATTN...WFO...OUN...SJT...LUB...AMA...

33710105 34180114 35250136 35770132 36160089 36070056
35800040 35250044 34910002 34759946 34479896 34049888
33669929 33379996 33270099 

WWWW