[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 131737
SWODY2
SPC AC 131736

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1236 PM CDT FRI MAY 13 2005

VALID 141200Z - 151200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 15 W
ART UCA 25 NE ABE 15 SSW PHL 25 WSW DOV 10 WNW DCA 45 W MRB 20 WSW
BKW 30 E CHA 10 SE HSV 35 SW MKL 25 NNE PAH 30 E IND 15 ENE TOL.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 70 E DUG 55 NW TCS 65
SW GNT 40 ESE INW 45 SSW PRC 30 S LAS 65 S NFL 10 N TVL 55 NW NID 35
NNW BFL 35 SSE UKI 10 SW EKA OTH 10 ESE OLM 25 WSW BLI ...CONT... 35
NNE HVR 50 W GGW 50 NNW SHR 50 E DGW 45 ESE CYS 35 NNW GLD 15 S EHA
35 WNW CDS 15 NNW DUA 20 N PGO 30 SE TBN 20 WSW SBN 10 SSW MTC
...CONT... 25 ENE EFK 20 ENE PWM.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE OH/TN VALLEYS INTO
PORTIONS OF THE NORTHEAST...

...SYNOPSIS...
POSITIVELY TILTED TROUGH...CURRENTLY EXTENDING FROM THE NRN PLAINS
INTO CO...WILL PHASE WITH AN UPSTREAM TROUGH DIGGING SEWD ACROSS
SOUTH CENTRAL CANADA ATTM.  THIS TROUGH WILL CONTINUE TO DEEPEN AND
TAKE ON A NEGATIVE TILT AS IT TRACKS ACROSS THE GREAT LAKES REGION. 
70-80 KT MID LEVEL FLOW ASSOCIATED WITH THE DEEPENING TROUGH AND A
LEAD SHORT WAVE TROUGH MOVING ACROSS THE OH VALLEY SATURDAY
AFTERNOON WILL PROVIDE FAVORABLE DEEP LAYER SHEAR FOR ORGANIZED
STORMS.

THUNDERSTORMS ARE EXPECTED TO BE ONGOING AT THE START OF THE PERIOD
ALONG THE COLD FRONT/AXIS OF SWLY LLJ FROM THE RED RIVER VALLEY/NRN
TX NEWD TO THE LOWER OH VALLEY/SRN GREAT LAKES.  OUTFLOW BOUNDARIES
ASSOCIATED WITH THIS CONVECTION AND THE COLD FRONT MOVING E AND S
WILL BE THE PRIMARY FOCI FOR STRONG TO SEVERE STORMS ON SATURDAY.

...OH/TN VALLEYS...
CLOUDINESS FROM ONGOING CONVECTION IS EXPECTED TO LIMIT THE DEGREE
OF SURFACE HEATING/BOUNDARY LAYER DESTABILIZATION ACROSS THE OH/TN
VALLEYS ON SATURDAY.  HOWEVER...MODEST MID LEVEL LAPSE RATES /AROUND
6.5 C/KM/ COMBINED WITH A NARROW AXIS OF SURFACE DEWPOINTS IN THE
MID 60S IN ALONG/E OF COLD FRONT SHOULD AID IN THE DEVELOPMENT OF
MODERATE INSTABILITY /MUCAPE 1000-1500 J/KG/.

OUTFLOW BOUNDARIES ASSOCIATED WITH ONGOING STORMS SHOULD PROVIDE A
FOCUS FOR THUNDERSTORM INITIATION AND/OR RE-INTENSIFICATION FARTHER
EAST INTO NY/PA...WITH ADDITIONAL MESOSCALE DETAILS IN THE NEXT
SECTION.  MODELS TEND TO AGREE THAT THUNDERSTORMS WILL DEVELOP
AND/OR INTENSIFY ALONG THE COLD FRONT AS IT MOVES EWD INTO THE
MODERATELY UNSTABLE AIR MASS...AND LARGE SCALE ASCENT INCREASES
DOWNSTREAM OF THE DEEPENING GREAT LAKES TROUGH AND LEAD TROUGH. 
DESPITE THE SOMEWHAT MODEST INSTABILITY...STRONG UNIDIRECTIONAL WIND
FIELDS /75 KT AT 500 MB AND 40-50 KT AT 850 MB/ SUGGEST THE PRIMARY
MODE OF CONVECTION WILL BE LINEAR.  A SQUALL LINE IS EXPECTED TO
TRACK ACROSS THE OH/TN VALLEYS... REACHING WRN NY TO ERN TN BY
15/00Z.

DEEP LAYER SHEAR FARTHER S ACROSS THE TN VALLEY WILL BE ORIENTED AT
MORE NORMAL TO THE COLD FRONT...SUGGESTING THE POTENTIAL FOR
DISCRETE STORMS IN ADVANCE OR EMBEDDED WITHIN THE SQUALL LINE.

IF STRONGER INSTABILITY IS EXPECTED IN LATER OUTLOOKS...THEN
PORTIONS OF THE OH/TN VALLEYS WOULD REQUIRE GREATER SEVERE
PROBABILITIES AND A POTENTIAL UPGRADE TO A MODERATE RISK...GIVEN THE
STRENGTH OF THE FORECAST WIND FIELDS.

...PORTIONS OF NY/ERN PA TO THE WRN CAROLINAS...
SURFACE HEATING ALONG AND IN LEE OF THE APPALACHIANS IS EXPECTED TO
SUPPORT AN AXIS OF MODERATE INSTABILITY FROM THE WRN CAROLINAS TO
MD/ERN PA AND SRN NY BY SATURDAY AFTERNOON.  THUNDERSTORMS ARE
EXPECTED TO DEVELOP AND/OR RE-INTENSIFY ALONG OUTFLOW BOUNDARIES
FROM MORNING CONVECTION.  ANOTHER FOCUS FOR THUNDERSTORMS WILL BE A
LEE SURFACE TROUGH.  STRONGEST DEEP LAYER SHEAR TO SUPPORT A SEVERE
THREAT WILL BE OVER NY INTO ERN PA/MD. THUS...THESE AREAS HAVE BEEN
ADDED TO THE SLIGHT RISK.

...PECOS AND RIO GRANDE VALLEYS OF TX INTO ERN NM...
WRN PORTION OF COLD FRONT WILL MOVE SWD ACROSS TX ON SATURDAY WITH
MOIST ESELY LOW-LEVEL FLOW AND STEEP LAPSE RATES SUPPORTING A
MODERATELY UNSTABLE AIR MASS ALONG AND S OF THE FRONT FROM SRN/SWRN
TX INTO ERN NM.  ALTHOUGH MID LEVEL FLOW WILL BE WEAK... ESELY
LOW-LEVEL WINDS COMBINED WITH THE WEAK WLY MID LEVEL WINDS SHOULD
RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR A FEW ORGANIZED STORMS
ALONG THE FRONT AND THE HIGHER TERRAIN OF SWRN TX INTO ERN NM.

..PETERS.. 05/13/2005

...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.