[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 280610
SWODY2
SPC AC 280609

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0109 AM CDT WED JUN 28 2006

VALID 291200Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE LOWER MO/MID MS/TN
VALLEYS...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF ND...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-ATLANTIC
REGION...

...SYNOPSIS...
UPPER PATTERN ACROSS THE U.S. WILL CONTINUE TO FEATURE A WRN RIDGE
AND ERN TROUGH...THOUGH SOME DEAMPLIFICATION OF THE FLOW FIELD
SHOULD OCCUR THIS PERIOD.  CORRESPONDINGLY...SURFACE PATTERN SHOULD
REMAIN GENERALLY WEAK...THOUGH A COLD FRONT MOVING TOWARD THE
ATLANTIC COAST...A SECOND BAROCLINIC ZONE ACROSS THE CENTRAL
PLAINS/MID MO VALLEY...AND A THIRD MOVING EWD ACROSS ND SHOULD EACH
SUPPORT CONVECTIVE DEVELOPMENT AND AN ASSOCIATED/LIMITED SEVERE
THREAT.

...LOWER MO/MID MS/TN VALLEYS...
AFTERNOON STORMS ARE FORECAST TO DEVELOP INVOF WEAK BAROCLINIC ZONE
FORECAST ACROSS THIS REGION...AS AIRMASS BECOMES MODERATELY UNSTABLE
DURING THE AFTERNOON.  CONVECTIVE DEVELOPMENT MAY BE AIDED BY WEAK
SHORT-WAVE TROUGH FORECAST BY NUMERICAL GUIDANCE TO MOVE SEWD ACROSS
THIS REGION WITHIN NWLY CYCLONIC FLOW ON THE REAR SIDE OF MAIN UPPER
TROUGH.

THOUGH CAP SHOULD BE STRONGER AND SHEAR WEAKER WITH WWD EXTENT INTO
THE CENTRAL PLAINS...THREAT APPEARS SUFFICIENT FROM NWRN MO SEWD
INTO MIDDLE TN TO WARRANT A SLIGHT RISK.  ALONG WITH POTENTIAL FOR
HAIL...ROUGHLY UNIDIRECTIONAL/NWLY FLOW WITH HEIGHT ALSO SUGGESTS
SOME POTENTIAL FOR DAMAGING WINDS WITH SMALL-SCALE LINES/BOWS WHICH
COULD DEVELOP.

OVERNIGHT...LOW-LEVEL JET SHOULD SUPPORT AN INCREASE IN WARM
ADVECTION -- AND SUBSEQUENT CONVECTIVE COVERAGE -- ACROSS THIS
REGION...PERHAPS SUPPORTING A CONTINUED SEVERE THREAT INTO THE
OVERNIGHT HOURS.

...ND...
EWD-MOVING COLD FRONT -- STRETCHING FROM THE CANADIAN PRAIRIE
PROVINCES SWD ACROSS ERN MT AT THE START OF THE PERIOD -- SHOULD
SHIFT EWD WITH TIME THROUGH THE DAY -- AHEAD OF MID-LEVEL SHORT-WAVE
TROUGH.  THOUGH LARGE-SCALE RIDGE ACROSS THE PLAINS SHOULD SUPPRESS
CONVECTIVE DEVELOPMENT FROM SD SWD...STORMS SHOULD DEVELOP ALONG
FRONT BY LATE AFTERNOON ACROSS PARTS OF NRN AND WRN ND...WHERE 50O
TO 1000 J/KG MEAN-LAYER CAPE IS ANTICIPATED.

THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SLY
FLOW AHEAD OF FRONT VEERING/INCREASING WITH HEIGHT TO AROUND 30 KT
FROM THE NW AT MID LEVELS WILL RESULT IN SHEAR SUPPORTIVE OF
MULTICELL/WEAK SUPERCELL STORMS.  THUS...THREAT FOR LOCALLY
STRONG/DAMAGING WINDS AND/OR HAIL WILL BE POSSIBLE WITH THE STRONGER
STORMS ACROSS THIS REGION. 

...MID-ATLANTIC REGION...
MODELS CONTINUE TO HINT THAT AN AREA OF SUFFICIENT DESTABILIZATION
AND AMPLE SHEAR MAY COEXIST DURING THE AFTERNOON ACROSS THE
MID-ATLANTIC REGION...NEAR COLD FRONT/AHEAD OF STRONG MID-LEVEL
SHORT-WAVE TROUGH APPROACHING THIS REGION DURING THE AFTERNOON.

PRESUMING THAT MORE WIDESPREAD PRECIPITATION WITHIN WARM CONVEYOR
BELT CAN SHIFT E OF THIS REGION RESULTING IN SUFFICIENT
INSTABILITY...THREAT FOR LOCALLY-SEVERE STORMS WOULD EXIST. 
THEREFORE...WILL RE-INTRODUCE A SLIGHT RISK ACROSS THIS
REGION...GIVEN APPARENT POTENTIAL FOR HAIL AND/OR LOCALLY-DAMAGING
WINDS DURING THE AFTERNOON/EARLY EVENING.

...ERN ID/SRN MT/NWRN WY...
SHORT-WAVE TROUGH IS FORECAST TO ROTATE NEWD ACROSS THIS REGION
DURING THE AFTERNOON...WITHIN SOMEWHAT ENHANCED FLOW ALOFT BETWEEN
RIDGE OVER THE ROCKIES AND TROUGH OVER WRN CANADA.  THOUGH DEGREE OF
MOISTURE/INSTABILITY REMAINS QUESTIONABLE ATTM...IT APPEARS THAT
SUFFICIENT COMBINATION OF SHEAR AND INSTABILITY MAY DEVELOP BY
AFTERNOON TO SUPPORT SOME THREAT FOR ISOLATED SEVERE STORMS.

...UPPER GREAT LAKES...
COOL /-16 TO -18/ MID-LEVEL TEMPERATURES ARE FORECAST ACROSS THIS
REGION WITHIN CIRCULATION OF LARGE-SCALE TROUGH.  SCATTERED
LOW-TOPPED/PRIMARILY DIURNAL THUNDERSTORMS ARE EXPECTED TO DEVELOP
DURING THE AFTERNOON...AS AIRMASS BECOMES MARGINALLY UNSTABLE. 
THOUGH GENERAL LACK OF INSTABILITY/SHEAR SHOULD PRECLUDE APPRECIABLE
SEVERE THREAT...A FEW STRONGER CELLS MAY PRODUCE SMALL HAIL --
POSSIBLY APPROACHING MARGINAL SEVERE CRITERIA.

..GOSS.. 06/28/2006