[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 221726
SWODY2
SPC AC 221725

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1225 PM CDT FRI OCT 22 2004

VALID 231200Z - 241200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 N
SLO 30 NE MMO 20 SW EAU 65 N EAU 10 NW IWD 30 S CMX 15 SSW ESC 25
NNW AZO 25 W MIE 25 SSW LUK 45 SW LOZ 25 NE HSV 35 WSW TCL 15 WNW
HEZ 45 NE LFK 40 NNE TYR 45 ENE LIT 30 N SLO.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM ELP 25 SSW HOB 15 ENE
BGS 25 ESE ABI 45 N FTW 10 N JLN 10 N OTM 30 S MCW 20 SSW FRM 40 NNE
AXN 35 ENE BJI INL ...CONT... 115 NE APN 10 ESE ERI 25 NNW EKN 15 NE
TRI 30 ENE ATL 25 SW MGM 20 SE BTR 30 WSW 7R4 ...CONT... 50 S VCT 15
S LRD.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 N FCA 40 N 3DU 55
SSW 3DU 40 NW BOI 40 WNW BNO 50 NW RDM 30 SSW AST.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER GREAT LAKES
SSWWD ACROSS THE OH / TN / LOWER MS VALLEYS INTO NERN TX...

...SYNOPSIS...
MID-LEVEL SHORT-WAVE TROUGH INITIALLY OVER THE PLAINS WILL WEAKEN
DURING THIS FORECAST PERIOD AS IT SHIFTS EWD TOWARD SHARP UPPER
RIDGE OVER THE ERN HALF OF THE CONUS.  MEANWHILE...LARGE UPSTREAM
TROUGH WILL DIG SEWD WITH TIME ACROSS THE WRN CONUS.

AT THE SURFACE...COLD FRONT ASSOCIATED WITH INITIAL SHORT-WAVE
TROUGH SHOULD EXTEND SSWWD FROM A SURFACE LOW OVER MN ACROSS THE MO
VALLEY AND INTO ERN OK / N TX AT THE START OF THE PERIOD.  THIS
FRONT IS FORECAST TO CONTINUE EWD ACROSS THE MID AND UPPER MS /
LOWER AND MID OH VALLEYS THROUGH THE PERIOD...WHILE LAGGING /
WEAKENING ACROSS N TX THROUGH THE SECOND HALF OF THE PERIOD.

...UPPER GREAT LAKES SWD ACROSS THE OH / TN / LOWER MS VALLEYS...
MAIN AREA OF CONVECTION THIS PERIOD IS FORECAST TO REMAIN WITHIN
WARM CONVEYOR / TROPICAL PLUME AHEAD OF MAIN SURFACE FRONT.  MODELS
SUGGEST THAT THIS BAND OF CONVECTION SHOULD INITIALLY EXTEND FROM LK
MI SWWD ACROSS THE MID MS VALLEY INTO AR / NERN TX...AND WILL THEN
SHIFT EWD ACROSS THE OH / TN / LOWER MS VALLEYS THROUGH THE
AFTERNOON.  

GIVEN THIS SCENARIO...WHICH SEEMS TO BE CONSISTENT WITH CURRENT
CONVECTIVE EVOLUTION...LITTLE POTENTIAL FOR DESTABILIZATION WILL
EXIST AHEAD OF CONVECTIVE BAND -- PARTICULARLY N OF THE OH VALLEY
WHERE STORMS WILL LIKELY REMAIN PRIMARILY ELEVATED.  THIS IS DUE TO
THE FACT THAT NOT ONLY WILL THE CONVECTIVE BAND OUTRUN REGION OF
STRONGER LOW-LEVEL MOISTURE ADVECTION...CONVECTION WILL ALSO BE
IMPINGING ON WARMER TEMPERATURES ALOFT / WEAK MID-LEVEL LAPSE RATES
ASSOCIATED WITH PERSISTENT ERN U.S. UPPER RIDGE.  THOUGH MODELS DO
INDICATE SOME DESTABILIZATION DURING THE AFTERNOON ALONG FRONT /
BEHIND INITIAL CONVECTIVE BAND...LITTLE CONVECTIVE REDEVELOPMENT IS
INDICATED BY THE MODELS ALONG FRONTAL ZONE.

DESPITE THESE NEGATIVES...STRONG / ROUGHLY UNIDIRECTIONAL DEEP-LAYER
WIND FIELD WILL PERSIST THROUGH THE AFTERNOON...SUPPORTIVE OF
SUPERCELLS OR WIND DAMAGE ALONG ANY LINEAR CONVECTIVE BANDS. 
ADDITIONALLY...ALTHOUGH FLOW SHOULD REMAIN ROUGHLY UNIDIRECTIONAL
ABOVE THE BOUNDARY LAYER...SOME VEERING IN THE 0-1 KM LAYER AS WELL
AS AN INCREASE IN WIND SPEED THROUGH THIS LAYER SHOULD RESULT IN
SUFFICIENT SHEAR FOR AT LEAST A LOW-PROBABILITY TORNADO THREAT.

ATTM...WILL MAINTAIN A FAIRLY LARGE SLIGHT RISK AREA TO INCLUDE BOTH
THE THREAT FOR DAMAGING WINDS OR AN ISOLATED TORNADO OR TWO WITHIN
PRE-FRONTAL CONVECTIVE BAND AS WELL AS THE POSSIBILITY OF SEVERE
STORM REDEVELOPMENT ALONG FRONT / BEHIND INITIAL BAND OF CONVECTION.


SEVERE THREAT WILL DECREASE DURING THE LATTER HALF OF THE PERIOD AS
WEAKENING UPPER TROUGH / WIND FIELD AND DIURNAL AIRMASS
STABILIZATION OCCUR.

..GOSS.. 10/22/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.