[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 041710
SWODY2
SPC AC 041709

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1109 AM CST FRI NOV 04 2005

VALID 051200Z - 061200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 50 N
CLE 50 NW HTS 45 ENE BWG 30 SSW DYR 30 NNW LIT 30 WNW HRO 20 WSW COU
25 S MKG 65 E BAX.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 NE MSS 10 SSE ELM
UNV 25 SSW EKN 15 NE TRI 35 ESE CHA 30 SSE HSV 30 E GWO 35 NNE MLU
DEQ 15 S TUL 25 WNW LWD 25 NNW FOD 20 WNW FRM 25 W MSP 10 SSW EAU 30
NE VOK 15 WNW MTW 20 SSE TVC 65 E APN.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN GREAT LAKES INTO
THE MID MS VALLEY...

...SYNOPSIS...
BROAD...CYCLONIC MID/UPPER-LEVEL FLOW REGIME IS FORECAST TO PERSIST
ACROSS THE CONUS THROUGH THE DAY 2 PERIOD.  WITHIN THIS
PATTERN...VIGOROUS SHORTWAVE TROUGH /NOW APPROACHING THE PACIFIC NW
COAST/ IS FORECAST TO INTENSIFY AND BECOME NEGATIVELY-TILTED AS IT
TRANSLATES FROM THE CNTRL PLAINS INTO THE GREAT LAKES. IN THE
LOW-LEVELS...PRIMARY BAROCLINIC ZONE WILL INITIALLY EXTEND FROM THE
SRN GREAT LAKES SWWD TO LOW PRESSURE OVER OK AND THEN INTO THE SRN
HIGH PLAINS.  THIS LOW PRESSURE WILL DEEPEN AS IT RAPIDLY DEVELOPS
NEWD ALONG FRONTAL ZONE INTO LOWER MI SATURDAY NIGHT.  AS THIS
OCCURS....TRAILING COLD FRONT WILL BEGIN TO ACCELERATE EWD THROUGH
THE MID MS OH VALLEYS.

...SRN GREAT LAKES/MIDDLE MS AND OH VALLEYS...

04/12Z SOUNDINGS ACROSS SRN PLAINS INTO LOWER MS VALLEY INDICATE THE
PRESENCE OF A STRONG CAP /ELEVATED MIXED-LAYER/ ATOP A
RETURNING...MODIFIED GULF AIR MASS.  PERSISTENT SWLY LOW-LEVEL FLOW
WILL ALLOW MOISTURE TO INCREASE BENEATH THIS STRONG CAP WITH SURFACE
DEWPOINTS INCREASING THROUGH THE 50S INTO LOWER 60S S OF FRONTAL
ZONE.  WHEN COUPLED WITH DAYTIME HEATING AND STEEPENING MID-LEVEL
LAPSE RATES...AIR MASS IS EXPECTED TO DESTABILIZE THROUGH THE DAY
WITH MLCAPES RANGING FROM 500-1000 J/KG OVER SRN LOWER MI TO AROUND
1500 J/KG OVER THE MIDDLE MS AND LOWER OH VALLEYS.

INCREASING LARGE-SCALE FORCING IN ADVANCE OF SHORTWAVE TROUGH AND
ASSOCIATED 70-80 KT MID-LEVEL JET STREAK ARE EXPECTED TO RESULT IN
CAP REMOVAL AND SUBSEQUENT STORM DEVELOPMENT BY MID/LATE AFTERNOON
ALONG FRONT...ESPECIALLY INVOF DEEPENING SURFACE LOW WHERE LOW-LEVEL
CONVERGENCE WILL BE ENHANCED.  DESPITE LARGELY UNIDIRECTIONAL SWLY
WIND FIELDS...SUFFICIENT VERTICAL SPEED SHEAR WILL SUPPORT SUPERCELL
STRUCTURES INITIALLY WITH CONVECTIVE MODE EVOLVING TO MORE LINEAR
WITH EMBEDDED BOWING STRUCTURES.  LARGE HAIL AND DAMAGING WINDS WILL
BE THE PRIMARY SEVERE WEATHER THREATS...THOUGH ISOLATED TORNADOES
WILL BE POSSIBLE WITH ANY SUPERCELLS WHICH CAN DEVELOP AHEAD OF
SURFACE LOW WHERE LOW-LEVEL SHEAR IS FORECAST TO BE CONSIDERABLY
STRONGER.

GIVEN THE RELATIVELY STRONG CAP AND ONLY MODEST LOW-LEVEL
MOISTURE...ANY ONGOING SEVERE THREAT SHOULD TEND TO DIMINISH
SATURDAY NIGHT AS THE BOUNDARY-LAYER COOLS AND CONVECTIVE INHIBITION
INCREASES.

..MEAD.. 11/04/2005

...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.