[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 290532
SWODY1
SPC AC 290531

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1231 AM CDT MON AUG 29 2005

VALID 291200Z - 301200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 SSW
HUM 15 SSW GWO 15 SSE MKL 15 WNW BNA 20 NW CSV 35 S TYS 25 NE ATL 10
SE AQQ.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 WSW JLN 25 S ICT
10 S HSI 15 S SUX 15 S FOD 20 E DSM 40 NNE SZL 20 WSW JLN.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SSW FHU 10 ENE SAD
40 SSE GNT SAF 35 WSW CAO 15 SW LBL 15 NNE GAG 40 N FSI 15 SSW MWL
50 S TYR TXK 50 SE VIH 10 ESE DNV 65 N MTC.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 NW ISN 4BQ 25 E
WRL 10 SW EVW 55 SE ELY 30 SW U31 55 ESE 4LW 60 SSW PDT 50 NW RDM 10
NNW ONP.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL/ERN GULF COAST
INTO THE TN VALLEY...

...SYNOPSIS...
PRIMARY FEATURE OF INTEREST DURING THE DAY 1 PERIOD WILL BE POWERFUL
HURRICANE KATRINA WHICH IS FORECAST TO MAKE LANDFALL NEAR THE MOUTH
OF THE MS RIVER...PRIOR TO MOVING NWD AND THEN NNEWD TO FAR NERN
MS/NWRN AL BY 30/12Z.  OTHERWISE...AMPLIFIED POLAR STREAM IS
FORECAST TO PERSIST ACROSS THE NRN TIER OF STATES WITH
MID/UPPER-LEVEL LOW MOVING SLOWLY EWD INTO WRN QUEBEC...AND MOBILE
UPPER TROUGH SHIFTING EWD INTO THE NRN ROCKIES.

IN THE LOW-LEVELS...WEAK BAROCLINIC ZONE FROM THE ERN GREAT LAKES
SWWD ALONG THE OH RIVER IS EXPECTED TO BE THE PRIMARY FOCUS OF A FEW
STRONG TO POTENTIALLY SEVERE STORMS THIS AFTERNOON INTO EVENING. 
FARTHER TO THE W...STRONG COLD FRONT ASSOCIATED WITH NRN ROCKIES
SYSTEM WILL PUSH EWD FROM THE PACIFIC NW INTO MT AND WY.

...CNTRL/ERN GULF COAST NWD INTO THE TN VALLEY...
A FAIRLY EXPANSIVE ENVELOPE OF MODERATE/STRONG LOW-LEVEL SHEAR ALONG
ERN SEMI-CIRCLE OF KATRINA IS FORECAST TO DEVELOP NWD ACROSS ERN
MS...AL AND PERHAPS INTO WRN GA TODAY AND TONIGHT.  PRIMARY
UNCERTAINTIES ATTM ARE HOW SYSTEM WILL EVOLVE /I.E. WHERE MAIN
CONVECTIVE BANDS WILL DEVELOP/ AND LOCATION AND DEGREE OF
DESTABILIZATION THAT WILL OCCUR WITHIN REGION OF FAVORABLE LOW AND
DEEP-LAYER VERTICAL SHEAR.  THEREFORE...A BROAD CORRIDOR OF LOW
TORNADO PROBABILITIES HAVE BEEN FORECAST.

...ERN GREAT LAKES INTO OH VALLEY...
AS MENTIONED ABOVE...WEAK FRONTAL BOUNDARY MOVING THROUGH THE REGION
IS EXPECTED TO SERVE AS A FOCUS FOR TSTM DEVELOPMENT THIS AFTERNOON
AND EVENING FROM OH INTO WRN PA/NY.  CURRENT IR SATELLITE IMAGERY
SHOWS CONSIDERABLE MID AND HIGH-LEVEL CLOUD COVER ACROSS REGION
WHICH MAY TEND TO SLOW THE DESTABILIZATION PROCESS TODAY. 
NONETHELESS...DIABATIC HEATING COUPLED WITH DEWPOINTS IN THE 60S TO
LOWER 70S WILL CONTRIBUTE TO POCKETS OF MODERATE INSTABILITY WITH
MLCAPES APPROACHING 1000-1500 J/KG.

DYNAMIC FORCING FOR ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH MOVING
THROUGH THE OH VALLEY ALONG WITH MODEST LOW-LEVEL CONVERGENCE SHOULD
SUPPORT AN INCREASE IN STORM COVERAGE AND INTENSITY THROUGH THE
AFTERNOON.  MODEST TO STRONG WSWLY MID AND HIGH-LEVEL WIND FIELDS
ALONG SRN PERIPHERY OF QUEBEC LOW WILL RESULT IN SUFFICIENT VERTICAL
SHEAR FOR A FEW ORGANIZED STORMS WITH THE PRIMARY THREAT BEING
ISOLATED DAMAGING WINDS.

...NRN ROCKIES...
WHILE LOW-LEVEL MOISTURE AND RESULTANT INSTABILITY WILL REMAIN QUITE
LIMITED AHEAD OF COLD FRONT...STRONG LARGE-SCALE FORCING ASSOCIATED
WITH UPPER-LEVEL TROUGH ALONG WITH STEEP LOW TO MID-LEVEL LAPSE
RATES WILL CONTRIBUTE TO SOME DESTABILIZATION OF PRE-FRONTAL AIR
MASS.  SHOULD DEEP...MOIST CONVECTION BE ABLE TO DEVELOP AND BECOME
SUSTAINED...SOME THREAT OF ISOLATED HAIL AND/OR DAMAGING WINDS WILL
EXIST GIVEN THE MODERATE/STRONG AMBIENT WIND FIELDS AND STEEP LAPSE
RATES.

..MEAD/TAYLOR.. 08/29/2005

...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.