[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 260529
SWODY1
SPC AC 260527

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1227 AM CDT MON SEP 26 2005

VALID 261200Z - 271200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 15 NE
ORF 55 N RWI 20 N RDU 35 NNW GSO 15 NW PSK 15 E EKN 10 WSW AOO 20 N
IPT 25 NW MSV PSF 10 SE ORH 20 NE BID.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 SSW GLS 40 W HOU
40 SE AUS 35 NW AUS 40 W ACT 25 SSW DAL 45 SSE MLC 20 SE FYV PAH 30
ESE MVN 20 SSW MTO 45 NW ALN 25 ENE IRK 40 NNE IRK 35 NW BRL 35 ENE
MLI 40 NW BEH 65 ESE OSC ...CONT... 95 W CAR 25 W 3B1 50 S BHB.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 SW SBA 50 E MRY 25
NNE SFO 40 N UKI 40 NNW SVE 35 WNW LOL 50 NNW U31 55 ESE U31 50 WNW
P38 35 SW DAG 35 SSW LGB 35 SW SBA.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE
MID-ATLANTIC AND SRN NEW ENGLAND...

...SYNOPSIS...
AMPLIFYING UPPER SHORTWAVE TROUGH ACROSS THE CNTRL PLAINS IS
EXPECTED TO TRANSLATE RAPIDLY EWD...REACHING THE OH VLY MON EVE AND
THE ERN SEABOARD BY 12Z TUE.  REMNANT RITA WILL BE EJECTED QUICKLY
FROM THE TN VLY EARLY IN THE PERIOD THEN ACROSS THE MID-ATLANTIC
REGION MON AFTN THEN OUT TO SEA BY TUE.  AT THE SURFACE...A COLD
FRONT WILL SETTLE SEWD FROM THE GRTLKS INTO NRN NEW ENGLAND...THE
UPPER OH VLY AND CNTRL/SRN PLAINS BY MON EVE.  A PRE-FRONTAL TROUGH
WILL EXIST ALONG THE LEE OF THE APPALACHIANS MON AFTN.

...MID/UPPER OH VLY EWD TO SRN NEW ENGLAND AND MID-ATLANTIC...
RICH LOW/MID-LEVEL MOISTURE WILL SURGE NWD FROM THE TN VLY/
CAROLINAS INTO THE MID-ATLANTIC AND NEW ENGLAND ON MON...AHEAD OF
THE APPROACHING COLD FRONT/UPPER TROUGH.  BY MID-AFTN...MID AND
UPPER 60S DEW POINTS SHOULD BE COMMON AS FAR N AS SRN NEW ENGLAND.

WIDESPREAD CONVECTION WILL BE ONGOING AT THE START OF THE PERIOD
FROM WRN NY THROUGH THE OH AND TN VLYS.  THIS WILL LIMIT
HEATING...AT LEAST INITIALLY...ACROSS THE WRN SLOPES OF THE
APPALACHIANS/OH VLY.  BUT...ALONG/E OF THE MOUNTAINS...THERE WILL
PROBABLY BE AT LEAST SOME HEATING...CONTRIBUTING TO WEAK
INSTABILITY.

COMBINATION OF UPPER SUPPORT FROM REMNANT RITA AND APPROACHING
MIDWEST TROUGH WILL BE SUFFICIENT FOR CONVECTION TO INTENSIFY AND/OR
DEVELOP VCNTY THE PRE-FRONTAL TROUGH FROM CNTRL PA SWD INTO ERN WV
BY MID-AFTN.  TSTMS WILL THEN LIKELY GROW STRONGER AS THEY APPROACH
SERN NY...ERN PA AND CNTRL VA BY LATE AFTN...EVOLVING INTO LINE
SEGMENTS.  AMBIENT LOW-LEVEL WIND FIELDS WILL ALREADY BE QUITE
STRONG AND TSTMS WILL LIKELY BRING THESE WINDS TO THE SURFACE WITH
ANY BOWING SEGMENTS.  THUS...DAMAGING WINDS WILL BE THE PRIMARY
THREAT.  THIS THREAT WILL PROBABLY SPREAD THROUGH THE COASTAL AREAS
LATE MON EVE AS A FORCED SQUALL-LINE TYPE OF SCENARIO SEEMS LIKELY.

MEANWHILE...LOW-TOPPED TSTMS MAY DEVELOP IN THE OH VLY MONDAY
AFTN...IN WAKE OF THE MORNING CONVECTION.  PRESENCE OF COLD AIR
ALOFT MOVING ATOP 60S DEW POINTS AND 60-65 KTS OF H5 CYCLONIC FLOW
MAY BE SUFFICIENT FOR A FEW STORMS TO ORGANIZE INTO LINE SEGMENTS. 
ISOLD DAMAGING WINDS APPEARS TO BE THE PRIMARY SEVERE THREAT.

...ARKLATEX REGION...
A COUPLE MEMBERS OF THE 21Z SPC SREF SUGGEST THAT ISOLD TSTMS COULD
DEVELOP ALONG THE COLD FRONT ACROSS PARTS OF THE ARKLATEX REGION MON
EVE.  CONFIDENCE IS NOT TERRIBLY HIGH ON THIS SCENARIO...BUT WEAK
HEIGHT FALLS...VERY WARM BOUNDARY LAYER AND PRESENCE OF MODEST
MOISTURE ARE POSITIVES FOR CONVECTION. MID-LEVEL LAPSE RATES WILL
NOT HAVE RECOVERED FROM RITA...BUT LARGE DEW POINT DEPRESSIONS AT
THE SURFACE MAY AUGMENT COLD DOWNDRAFT PRODUCTION/ISOLD DAMAGING
WIND GUSTS.

..RACY/GUYER.. 09/26/2005

...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.