SPC AC 080551
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CDT SAT JUL 08 2006
VALID 091200Z - 101200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN GREAT
LAKES...
...SYNOPSIS...
MODELS ARE IN AGREEMENT WITH THE EVOLUTION OF THE UPPER PATTERN FOR
THE DAY 2 PERIOD...AS A STRONG/SOMEWHAT COMPACT SHORT WAVE TROUGH...
NOW LOCATED OVER ALBERTA /NEAR EDMONTON/...TRACKS SEWD ACROSS THE
GREAT LAKES REGION ON SUNDAY INTO EARLY MONDAY. ERN U.S. TROUGH IS
PROGGED TO WEAKEN AS PRIMARY EMBEDDED SHORT WAVE TROUGH...CURRENTLY
LOCATED OVER VA/NC...DE-AMPLIFIES AND LIFTS NEWD ACROSS THE NERN
STATES. IN THE WEST...A SHORT WAVE TROUGH IS EXPECTED TO TRACK FROM
UT NE TOWARD THE NRN HIGH PLAINS...WHILE WEAKER IMPULSES MOVE ENEWD
ACROSS THE CENTRAL/SRN HIGH PLAINS.
...LOWER MI/SERN WI/NRN IL/NRN IND/NWRN OH...
IN THE LOW LEVELS...A PRE-FRONTAL TROUGH IS EXPECTED TO EXTEND FROM
NRN LOWER MI SWWD THROUGH NRN IL TO LOWER MO RIVER VALLEY AT 12Z
SUNDAY. SURFACE LOW ASSOCIATED WITH THE ALBERTA SHORT WAVE TROUGH
IS PROGGED TO DEVELOP SEWD INTO LOWER MI SUNDAY AFTERNOON AND THEN
TRACK EWD INTO SRN/SERN ONTARIO SUNDAY NIGHT. TRAILING COLD FRONT
WILL MOVE SEWD ACROSS THE GREAT LAKES REGION AND SWD INTO THE MID MS
VALLEY AND CENTRAL PLAINS. LOW LEVEL WAA MAY BE AIDING ONGOING
THUNDERSTORM ACTIVITY ALONG THE EXTENT OF THE PRE-FRONTAL TROUGH AT
12Z SUNDAY. AIR MASS DESTABILIZATION IS EXPECTED IN THE WAKE OF
THIS EARLY ACTIVITY AS IT MOVES ENEWD...WITH MODERATE INSTABILITY
DEVELOPING BY SUNDAY AFTERNOON AHEAD OF THE PROGRESSIVE COLD FRONT.
FORCING FOR ASCENT AHEAD OF THE MID/UPPER LEVEL TROUGH IS EXPECTED
TO SPREAD ACROSS THE SLIGHT RISK AREA DURING PEAK HEATING RESULTING
IN THUNDERSTORM DEVELOPMENT ALONG THE COLD FRONT.
MODELS DIFFER IN THE SRN EXTENT OF STRONG WNWLY MID LEVEL WINDS
/40-50 KT/ ACCOMPANYING THE SHORT WAVE TROUGH...WITH THE NAM BEING
FARTHEST S ACROSS THE SRN PART OF THE SLIGHT RISK AREA.
HOWEVER...GIVEN MODERATE INSTABILITY...SWLY LOW LEVEL WINDS BENEATH
MODERATE WNWLY FLOW WILL RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR
STORM ORGANIZATION...WITH MODELS SUGGESTING THE POTENTIAL FOR A
SQUALL LINE ALONG THE COLD FRONT. DEEP LAYER SHEAR WILL ALSO BE
STRONG ENOUGH FOR SUPERCELLS.
...ERN PA TO SERN NY/SWRN NEW ENGLAND...
ASCENT AHEAD OF THE ERN U.S. MID LEVEL CIRCULATION WILL SPREAD NEWD
ACROSS ERN PA INTO SERN NY/SWRN NEW ENGLAND SUNDAY AFTERNOON AIDING
IN SCATTERED THUNDERSTORM DEVELOPMENT ACROSS THESE AREAS. ALTHOUGH
DEEP LAYER SHEAR SHOULD BE SUFFICIENT FOR SOME STORM ORGANIZATION...
MARGINAL INSTABILITY WILL LIKELY LIMIT THE SEVERE THREAT WITH THIS
ACTIVITY. COLD POCKET /-14 C AT 500 MB/ WITH THE MID LEVEL IMPULSE
AND STEEP LAPSE RATE ENVIRONMENT SUGGEST A POTENTIAL FOR A FEW
STORMS PRODUCING ISOLATED HAIL/STRONG WIND GUSTS.
...SWRN KS SWD TO TX PANHANDLE...
MODELS SUGGEST THUNDERSTORMS WILL BE LIKELY ACROSS MUCH OF THE
CENTRAL/SRN ROCKIES EWD INTO PARTS OF THE CENTRAL AND SRN HIGH
PLAINS DURING DAY 2. ALTHOUGH INSTABILITY IS EXPECTED TO BE
GENERALLY MARGINAL ACROSS MUCH OF THESE AREAS...STRONGER DEEP LAYER
SHEAR EXPECTED ACROSS SWRN KS INTO THE TX PANHANDLE MAY RESULT IN A
FEW ORGANIZED STRONG TO SEVERE STORMS. A STRENGTHENING SLY LLJ
ACROSS THE SRN PLAINS SUNDAY NIGHT SHOULD SUPPORT UPSCALE GROWTH OF
THE ACTIVITY OVER SWRN KS TO THE TX PANHANDLE INTO AN MCS ACROSS
PARTS OF KS AND NRN OK.
..PETERS.. 07/08/2006
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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