[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 202357
SWOMCD
SPC MCD 202357 
KSZ000-OKZ000-TXZ000-210130-

MESOSCALE DISCUSSION 0614
NWS STORM PREDICTION CENTER NORMAN OK
0657 PM CDT WED APR 20 2005

AREAS AFFECTED...ERN TX PNHDL...NWRN TX...WRN OK...SWRN/SCNTRL KS

CONCERNING...SEVERE THUNDERSTORM WATCH 169...

VALID 202357Z - 210130Z

SVR TSTM WATCH 169 CONTINUES THROUGH 04Z WITH LARGE HAIL AND
DAMAGING WINDS THE MAIN THREATS.

LOW-AMPLITUDE SUB-TROPICAL IMPULSE PROVIDED SUFFICIENT BACKGROUND
LARGE SCALE ASCENT TO AID IN TSTM INITIATION ALONG THE DRYLINE
THIS AFTERNOON FROM THE CAPROCK OF THE TX PNHDL NWD INTO SWRN KS. 
VWP/PROFILERS EXHIBIT SOMEWHAT WEAK 0-6KM PROFILES /LESS THAN 25
KTS/...BUT HIGH LEVEL FLOW IS STRONG AIDING IN ANVIL LEVEL VENTING. 
MOREOVER...STEEP LOW/MID-LEVEL LAPSE RATES AND RECENT BACKING OF THE
NEAR GROUND FLOW HAVE BEEN FAVORABLE FOR SUPERCELLS.  

STRONGEST SUPERCELL HAS BEEN PERSISTENT 25W OF KCDS...WITH THE RIGHT
MOVING MEMBER REGENERATING OVER NEARLY THE SAME AREA AND LEFT-MOVING
MEMBERS MOVING NWD INTO THE NERN TX PNHDL.  DOWNSTREAM...ANVILS HAVE
PROBABLY ALTERED THE CINH BY COOLING THE TOP OF THE CAPPING LAYER
SUFFICIENTLY FOR RAPID TSTM DEVELOPMENT INTO SWRN OK.  FARTHER N...A
COUPLE OF SUPERCELLS AND THEIR RESPECTIVE LEFT-RIGHT MOVING MEMBERS
CONTINUE TO EVOLVE OVER SWRN KS.

PRIND THAT THE DRYLINE WILL EVENTUALLY BEGIN TO OSCILLATE BACK
WWD...AIDED BY ANY OUTFLOW BOUNDARIES. STORMS OVER SWRN OK WILL
LIKELY MOVE/DEVELOP EWD INTO WCNTRL OK.  BUT...THE INFLOW
TRAJECTORIES WILL BECOME INCREASINGLY MORE STABLE...AT LEAST FOR
STORMS ON THE SRN END OF THE WW.  FARTHER N...AXIS OF MOST UNSTABLE
AIR EXTENDS NWD INTO SCNTRL KS AND IT IS POSSIBLE THAT STORMS MAY
HAVE A LONGER LIFE FROM NWRN OK INTO SCNTRL/SWRN KS THIS EVENING. 
ANY STORM WILL BE CAPABLE OF LARGE HAIL AND GUSTY WINDS.  ISOLD
TORNADOES WILL BE POSSIBLE WHERE 1/ LOCAL BOUNDARY LAYER IS
MOISTENED/COOLED /IE LOWER LCLS/ AND 2/ BOUNDARY INTERACTIONS OCCUR.

..RACY.. 04/20/2005

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

ATTN...WFO...ICT...OUN...DDC...LUB...AMA...

33450133 37960016 37919791 33539920 

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