[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 231955
SWODY1
SPC AC 231953

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT SUN APR 23 2006

VALID 232000Z - 241200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN HIGH
PLAINS...CNTRL PLAINS...OZARKS AND THE LWR OH VLY...

...OZARKS EWD INTO LWR OH/TN VLYS THIS AFTN/EVE...
UPPER LEVEL JETSTREAK TIED TO THE GRTLKS UPPER LOW HAS MAINTAINED A
SWLY LLJ ACROSS THE SRN PLAINS INTO THE OZARKS THIS AFTN.  UNSTABLE
PARCELS HAVE BEEN REACHING THEIR LFC ACROSS CNTRL/SWRN MO AND NERN
OK AND MOSTLY ELEVATED TSTMS HAVE BEEN PRODUCING SEVERE HAIL THIS
AFTN.  THOUGH THE HIGHER PROBABILITIES FOR SEVERE WEATHER WILL EXIST
CLOSER TO THE INSTABILITY AXIS UPSTREAM...A FEW STRONGER STORMS ARE
YET POSSIBLE EWD ACROSS THE TN/LWR OH VLYS THROUGH EVENING.

...CNTRL PLAINS TO THE OZARKS LATE THIS AFTN/TONIGHT...
WATER VAPOR IMAGERY SHOWS A WEAK IMPULSE ROTATING NEWD ACROSS THE
SRN ROCKIES THAT WILL MOVE INTO ERN CO LATER THIS EVENING.  LARGE
SCALE ASCENT ASSOCIATED WITH THIS FEATURE PROBABLY HAS CONTRIBUTED
TO THE CONSIDERABLE HIGH-BASED CONVECTION OVER NERN NM AND ERN CO
THIS AFTN.

SFC ANALYSIS SHOWS THAT THE DRY HIGH PLAINS BOUNDARY LAYER WAS
ADVECTING NEWD INTO THE NRN TX PNHDL AND SWRN KS WITH STRONGEST MASS
CONVERGENCE DEVELOPING VCNTY THE WARM FRONT ACROSS WCNTRL-NCNTRL KS.
 THE WARM SECTOR CONTINUES TO DESTABILIZE OWING TO UNABATED HEATING
AND SFC DEW POINTS REMAINING IN THE MID-UPPER 50S.  AS CINH
CONTINUES TO ERODE...THE HIGH-BASED CONVECTION APPROACHING FROM THE
WEST WILL LIKELY GROW INTO THE UNSTABLE BOUNDARY LAYER AND INTENSIFY
OVER WCNTRL/NWRN KS.  OTHER STORMS WILL TEND TO DEVELOP ALONG/SWWD
ALONG THE DRYLINE INTO SWRN KS AND THE TX/OK PNHDLS DURING THE
EVENING.

VERTICAL SHEAR REMAINS MARGINAL WITH MOST PROFILERS IN KS/OK SHOWING
30-35 KTS OF 6KM SHEAR.  THUS...TSTMS WILL PROBABLY TEND TO CLUSTER
AND BECOME OUTFLOW-DOMINANT WITH MAINLY LARGE HAIL AND DAMAGING WIND
THREATS.

GIVEN THE MAINTENANCE OF A SLY LLJ IMPINGING ON THE WARM FRONT
OVERNIGHT...IT IS REASONABLE TO EXPECT TSTMS TO DEVELOP ESEWD ACROSS
CNTRL KS AND INTO PARTS OF THE OZARKS THROUGH THE OVERNIGHT. 
STRONGER STORMS WILL CONTINUE TO HAVE A HAIL/GUSTY WIND THREAT. 
STORMS FARTHER S SHOULD WEAKEN WITH TIME AS THE DRYLINE RETREATS AND
MOST OF THE MASS CONVERGENCE BECOMES CONFINED NE OF THE REGION.

...SRN HIGH PLAINS...
LOW-LEVEL MOISTURE CONTINUES TO HUG THE HIGHER SWRN TX/SERN NM
TERRAIN WHERE DIURNAL UPSLOPE CIRCULATION IS BEING ENHANCED BY AN
UPSTREAM MEXICAN SHORTWAVE TROUGH.  STRONG HEATING AND WEAK LARGE
SCALE ASCENT SHOULD BE SUFFICIENT FOR MOUNTAIN CONVECTION TO SURVIVE
ONTO THE PLAINS AGAIN THIS EVENING.  THOUGH MID-AFTN VERTICAL SHEAR
IS MARGINAL...THE FLOW ALOFT SHOULD INCREASE AS THE MEXICAN
SHORTWAVE APPROACHES THE REGION.  THUS...SUPERCELLS WILL BE POSSIBLE
WITH LARGE HAIL AND DAMAGING WINDS.

...NRN PA/WRN NY...
H5 SPEED MAX ROTATING AROUND THE PERIPHERY OF THE UPPER LOW
CONTINUES TO DIG INTO THE UPPER OH VLY.  RESIDUAL BOUNDARY LAYER DEW
POINTS IN THE UPPER 40S BENEATH STEEP MID-TROPOSPHERIC LAPSE RATES
AND LOCAL SURFACE CONVERGENCE ALONG ATTENDANT FRONT WILL BE
FAVORABLE FOR DIURNALLY-ENHANCED TSTMS PRODUCING MARGINALLY SEVERE
HAIL OR GUSTY WINDS ACROSS MAINLY WRN NY THIS EVENING.

...NRN GRT BASIN...
VORT MAX ROTATING AROUND THE COMPLEX UPPER LOW OVE SRN NV IS
ENHANCING CONVECTION WITHIN A BROAD DEFORMATION ZONE ACROSS
CNTRL/NERN NV THIS AFTN.  STEEP LAPSE RATES AND PRESENCE OF DEEP
ASCENT MAY AUGMENT HAIL PRODUCTION WITH ISOLD STORMS.

..RACY.. 04/23/2006