[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 171744
SWODY2
SPC AC 171743

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1243 PM CDT WED AUG 17 2005

VALID 181200Z - 191200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM MKG
GRR 35 WNW FDY DAY LUK 40 SSE SDF BWG PAH CGI VIH 50 N SZL 55 ENE
OMA FRM MKT MSP EAU CWA MTW MKG.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SE IPL EDW FAT TVL
RNO WMC OWY SUN BTM HLN LWT MLS DIK 70 NE MOT ...CONT... 40 NNW BUF
PSB MRB CHO LYH DAN RDU GSB HSE ...CONT... LRD COT SAT AUS SHV 35
ENE TXK FSM EMP BIE LNK OLU BUB BBW MCK EHA MAF 40 S P07.

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS SERN MN/IA TO WRN
OH/NRN KY...

...SYNOPSIS...
PROGRESSIVE NRN STREAM FLOW PATTERN WILL BE DOMINATED BY MID/UPPER
LEVEL LOW NOW TAKING SHAPE OVER SRN BC AND PACIFIC NW. THIS FEATURE
IS PROGGED TO TURN EWD ACROSS SRN ALTA AND SRN SASK THROUGH
PERIOD...WITH ASSOCIATED TROUGH SWD INTO N-CENTRAL ROCKIES.  AS THIS
GRADUALLY OCCURS...LEADING SHORTWAVE TROUGH -- NOW EVIDENT IN
VWP/PROFILER DATA AND MOISTURE CHANNEL IMAGERY OVER ERN WY -- IS
EXPECTED TO EJECT EWD OVER UPPER MS VALLEY AND LM REGION.

QUASISTATIONARY SFC FRONTAL ZONE -- NOW ANALYZED ACROSS NRN/ERN
MT...SRN ND AND NRN MN -- IS EXPECTED TO BECOME COLD FRONT AS NWRN
TROUGH/LOW APCH AREA...MOVING SEWD ACROSS NRN/CENTRAL PLAINS AND NRN
MN.  ATTACHED SFC LOW SHOULD MOVE EWD ACROSS NRN MN...WHILE MIDLEVEL
TROUGH MOVES OVHD.  WARM FRONT SHOULD LIFT NWD OVER PORTIONS
IA/WI/IL/LM AND LOWER MI THROUGH PERIOD.

...MID MS VALLEY...SRN GREAT LAKES...LOWER OH VALLEY...
STRONGEST DEEP-LAYER ASCENT IS EXPECTED TO OCCUR INVOF SFC LOW...AND
ALONG AND N OF WARM FRONT OVER UPPER MIDWEST.  HOWEVER...TIGHTEST
FLOW GRADIENTS ALOFT AND STRONGEST DEEP-LAYER SHEAR IS EXPECTED TO
BE GENERALLY S OF SFC WARM FRONT ACROSS WARM SECTOR...FROM ERN IA
ACROSS WRN IL BY AFTERNOON.  HORIZONTAL DISPLACEMENT BETWEEN
STRONGEST PROGGED LIFT AND STRONGEST BUOYANCY/SHEAR LENDS SOME
UNCERTAINTY ABOUT LOCATION/COVERAGE OF CONVECTION..AND WHERE TO
ASSIGN HIGHER PROBABILITIES WITHIN BROAD 15% ENVELOPE. 
HOWEVER...WEAK CAP IS EVIDENT IN MODIFIED ETA FCST
SOUNDINGS...SUGGESTING ANY CONVECTION THAT DOES DEVELOP WILL BECOME
SEVERE WITH DAMAGING GUSTS, HAIL AND A FEW TORNADOES POSSIBLE. 
ALSO...OUTFLOW BOUNDARY FROM POSSIBLE MCS OVERNIGHT DAY-1 MAY MAKE
PROFILES MORE FAVORABLE ON MESOSCALE AND OPTIMAL SEVERE THREAT AREA
MORE PRECISELY DEFINED.

GREATEST SUPERCELL POTENTIAL SHOULD BE INVOF WARM FRONT OR OUTFLOW
BOUNDARY WHERE SFC FLOW IS MOST STRONGLY BACKED...OPTIMALLY
ENLARGING LOW LEVEL HODOGRAPHS WHERE THERE STILL IS SUBSTANTIAL
SFC-BASED INSTABILITY. MODIFIED MODEL SOUNDINGS SHOW 0-1 KM SRH
200-300 J/KG NEAR WARM FRONT...AND A STILL-FAVORABLE 100-200 J/KG
SWD TOWARD NERN MO/WRN IL DESPITE NEARLY UNIDIRECTIONAL DEEP-LAYER
FLOW S OF WARM FRONT.  WARM SECTOR EFFECTIVE SHEARS MAY REACH 45-50
KT.  BUOYANCY WILL BE MAXIMIZED S OF WARM FRONT...AS VERY RICH
BOUNDARY LAYER MOISTURE AND SFC DIABATIC HEATING CONTRIBUTE TO
MLCAPES 2000-3000 J/KG.  STRONGEST DEEP-LAYER SHEAR WILL SHIFT EWD
ACROSS IL/INDIANA DURING EVENING AND OVERNIGHT.

AFTERNOON ACTIVITY MAY EVOLVE INTO EVENING/OVERNIGHT COMPLEX THAT
WOULD MOVE ACROSS PORTIONS IL/WI/LM AND POSSIBLY LOWER MI BEFORE
WEAKENING.  DAMAGING GUSTS AND OCCASIONAL HAIL ARE POSSIBLE.

...UPPER MIDWEST TO WY...
SCATTERED TO WIDELY SCATTERED TSTMS ALSO ARE POSSIBLE ALONG AND
BEHIND FCST SFC COLD FRONT...WITH ACTIVITY OVER ERN WY/SERN MT AIDED
BY POSTFRONTAL UPSLOPE COMPONENT TO BOUNDARY LAYER WINDS. 
DEEP-LAYER SHEAR WILL BE FAVORABLE AND INCREASING THROUGHOUT DAY
WITH APCH OF STRONG NWRN TROUGH...I.E. 50-60 KT OF 0-6 KM AND
EFFECTIVE SHEARS PROGGED IN NERN WY.  ALTHOUGH LOW LEVEL MOISTURE
AND INSTABILITY WILL BE MORE LIMITED IN THIS AREA...STEEPENING
MIDLEVEL LAPSE RATES MAY YIELD ENOUGH BUOYANCY TO SUPPORT HAIL/WIND
THREAT WITH STRONGER CELLS.

..EDWARDS.. 08/17/2005

...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.