[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 141720
SWODY2
SPC AC 141719

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1219 PM CDT WED SEP 14 2005

VALID 151200Z - 161200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM CLL
AUS JCT 35 S MAF HOB CVS CDS 30 SW SPS 45 SW PRX TYR 40 W LFK CLL.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SE OAJ 30 NW EWN
50 NE RWI 60 SW RIC DAN HKY ANB 0A8 35 ESE POE 60 SSW CLL 50 SSW JCT
70 ENE P07 35 SSW MAF 30 WSW HOB 55 NE 4CR LVS RTN CAO 20 NW GAG CNU
HUF CAK FKL BFD SYR MSS.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 NW CMX 65 SSE DLH
MKT OTG FSD MHE HON ABR JMS 65 NNE BIS P24 GDV LWT GTF 105 WNW CTB.

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL/WRN TX...

...SYNOPSIS...
MID/UPPER LEVEL PATTERN IS FCST TO BECOME LESS AMPLIFIED THROUGH
PERIOD WITH LARGEST HEIGHT RISES OCCURRING ACROSS SRN/CENTRAL
ROCKIES AND MUCH OF GREAT PLAINS.  POSITIVELY TILTED SHORTWAVE
TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY FROM CENTRAL CO
SWWD OVER 4-CORNERS REGION -- IS EXPECTED TO MOVE EWD ACROSS
LOWER/MID MS VALLEY BY END OF PERIOD.  MORE AMPLIFIED SPECTRAL/ETA
DEPICTIONS OF THIS PERTURBATION ARE CONSISTENT WITH MAJORITY OF 09Z
SREF MEMBERS AND CURRENT SATELLITE TRENDS...AND ARE PREFERRED.

AT SFC...OUTFLOW-MODULATED BAROCLINIC ZONE IS ANALYZED FROM LOWER MI
ACROSS SWRN MO TO SWRN OK AND SRN TX PANHANDLE.  FRONT IS EXPECTED
TO DRIFT SWD OVER SRN PLAINS MAINLY INFLUENCED BY ADDITIONAL
OUTFLOWS PRODUCED BY CONVECTION LATE DAY-1 INTO EARLY DAY-2 PERIOD. 
WEAK FONTAL-WAVE CYCLOGENESIS IS EXPECTED AHEAD OF MIDLEVEL
TROUGH...WITH RESULTANT LOW MOVING NEWD ALONG FRONT FROM AR UP OH
VALLEY.

...SRN PLAINS...
SCATTERED TSTMS ARE EXPECTED TO BE ONGOING EARLY IN PERIOD N OF SFC
FRONT...MAIN THREAT BEING MARGINALLY SEVERE HAIL IN ENVIRONMENT OF
FAVORABLE ELEVATED/EFFECTIVE SHEAR AND MUCAPE. PRIMARY SEVERE
POTENTIAL...HOWEVER...SHOULD BE FROM MIDAFTERNOON INTO LATE EVENING
CLOSE TO FRONT...INCLUDING SUPERCELLS WITH LARGE HAIL AND SEVERE
GUSTS.

ONE LIMITING FACTOR WILL BE PRESENCE OF MIDLEVEL HEIGHT RISES AMIDST
SHORTWAVE RIDGING...DURING AFTERNOON...WHICH MAY LEAD TO SOME
WARMING ABOVE BOUNDARY LAYER AND RESTRICT CONVECTIVE COVERAGE. 
HOWEVER...ASSOCIATED VEERING OF MIDLEVEL FLOW TO WLY/WNWLY WILL
AUGMENT DEEP-LAYER SHEAR PROFILES...PARTICULARLY ALONG AND N OF SFC
FRONT WHERE SFC WINDS BEAR STRONG ELY COMPONENT.  MODIFIED ETA
SOUNDINGS FROM RED RIVER REGION WWD PAST CAPROCK AREA AND SWWD
ACROSS NRN PERMIAN BASIN INDICATE EFFECTIVE SHEARS 60-70 KT AND 0-6
KM LAYER SHEAR 50-60 KT...THOUGH WEAK WINDS IN 850-700 MB LAYER
IMPOSE SOME CONSTRAINTS ON HODOGRAPH SIZE AND STORM-RELATIVE FLOW. 
SMALL CORRIDOR OF GREATER SEVERE PROBABILITIES MAY BECOME EVIDENT
WITHIN THIS BROAD SLGT RISK AREA...BUT ACTUAL FOCI FOR CONVECTION
WILL BE STRONGLY DEPENDENT UPON MESOBETA SCALE OUTFLOW PROCESSES YET
TO OCCUR.  THEREFORE BROAD/15 PERCENT PROBABILITIES ARE GIVEN ATTM.

...TN/OH VALLEY REGION TO NERN CONUS...
SCATTERED TO WIDELY SCATTERED TSTMS ARE POSSIBLE INVOF FRONTAL ZONE.
 SEVERE POTENTIAL APPEARS MARGINAL OVERALL BECAUSE OF WEAK
THERMODYNAMICS...SFC AND ALOFT...AND ALSO IS CONDITIONAL ON
MESOSCALE PROCESSES.  THEREFORE PROBABILITIES ARE KEPT BELOW
CATEGORICAL THRESHOLDS ATTM.  MESOSCALE AREA JUST AHEAD OF
FRONTAL-WAVE LOW MAY REPRESENT PRIMARY POTENTIAL FOR STRONG-SEVERE
STORMS BECAUSE OF ISALLOBARICALLY FORCED LOW LEVEL SHEAR
ENHANCEMENTS...ESPECIALLY IF DEPTH OF LOW RESEMBLES SPECTRAL PROGS
MORE THAN ETA. FCST SOUNDINGS INDICATE SMALL DEEP-TROPOSPHERIC
LAPSE RATES DESPITE SOME ENHANCED LARGE SCALE ASCENT AHEAD OF
MIDLEVEL TROUGH.  THEREFORE BUOYANCY WILL DEPEND GREATLY ON PRESENCE
OF LATE MORNING/AFTERNOON INSOLATION...ITSELF QUITE CONDITIONAL
BECAUSE OF LIKELIHOOD OF CLOUD/PRECIP DEBRIS FROM PRIOR AND/OR
UPSTREAM CONVECTION.

...COASTAL ERN NC...
BASED ON NHC PROGS...GREAT MAJORITY OF NERN QUADRANT OF OPHELIA WILL
BE OFFSHORE EARLY IN PERIOD...WITH COVERAGE OVER LAND SHRINKING
DURING DAY.  GIVEN THIS FACTOR ALONG WITH EXPECTED WEAK
INSTABILITY...TORNADO RISK APPEARS TOO MINIMAL ATTM TO WARRANT 5
PERCENT SEVERE RISK OR CATEGORICAL OUTLOOK.

REF LATEST NHC BULLETINS -- I.E. WMO HEADER WTNT21 KNHC -- FOR
LATEST TRACK/INTENSITY FORECASTS AND TROPICAL WATCHES/WARNINGS ON
OPHELIA.

..EDWARDS.. 09/14/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.