[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 190538
SWODY2
SPC AC 190537

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1237 AM CDT WED JUL 19 2006

VALID 201200Z - 211200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE LOWER GREAT LAKES
AND OH/MID MS VALLEY REGION...

...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN AND CNTRL HIGH
PLAINS...

...SYNOPSIS...

DOMINANT HIGH PRESSURE WILL BE SUPPLANTED BY BROAD UPPER TROUGHING
WITH SEVERAL DISTINCT SIGNIFICANT SHORTWAVE TROUGHS FROM THE NRN
PLAINS TO THE OH VALLEY DURING THE NEXT FEW DAYS.  THIS TRANSITION
WILL LIKELY RESULT IN CONSIDERABLE AREAL COVERAGE OF DEEP CONVECTION
ALONG THE LEADING EDGE OF ADVANCING FRONTAL ZONE.

...LOWER GREAT LAKES/OH VALLEY/MID MS VALLEY...

MCS WILL LIKELY BE ONGOING AT THE BEGINNING OF THE PERIOD FROM LOWER
MI INTO NERN IL...AN EXTENSION OF DAY1 COMPLEX THAT SHOULD SPREAD
SEWD ACROSS THE UPPER GREAT LAKES.  DAY2 CONVECTIVE EVOLUTION MAY BE
SOMEWHAT MODULATED BY INTENSITY OF EARLY MORNING ACTIVITY.  THERE IS
A DISTINCT POSSIBILITY THAT AN ELONGATED SEVERE SQUALL LINE WILL
PROPAGATE SEWD ACROSS THE OH VALLEY AHEAD OF WELL DEFINED UPPER
TROUGH.  STEEP LAPSE RATE PLUME AND MODERATE BOUNDARY LAYER
INSTABILITY SHOULD ENHANCE THE POTENTIAL FOR DAMAGING WINDS AS THIS
ACTIVITY SPREADS ACROSS IND/OH...NEWD INTO UPSTATE NY. CONVECTION
WILL STRUGGLE TO SPREAD/DEVELOP SWWD INTO MO WHERE STRONG CAP AND
LESS FAVORABLE THERMODYNAMIC PROFILES WILL PROVE HOSTILE TO BOUNDARY
LAYER DEVELOPMENT...IN ADDITION TO NEGLIGIBLE INFLUENCE FROM UPPER
TROUGH.

...NRN/CNTRL HIGH PLAINS...

SECONDARY SPEED MAX/SHORTWAVE TROUGH WILL SUPPRESS UPPER RIDGE OVER
THE HIGH PLAINS THURSDAY.  THIS FEATURE WILL UNDOUBTEDLY AID
VERTICAL ASCENT FROM ERN MT/WRN DAKOTAS...SWD INTO THE NEB PANHANDLE
WHERE ELY COMPONENT TO BOUNDARY LAYER FLOW WILL ENHANCE UPSLOPE
COMPONENT AND LOW LEVEL SHEAR. FORECAST SOUNDINGS FOR THIS REGION
STRONGLY SUGGEST SUPERCELLS WILL DEVELOP BY MID
AFTERNOON...INITIALLY ACROSS NRN AREAS...WITH SEWD MOVEMENT EXPECTED
DURING THE OVERNIGHT HOURS.  INCREASING LLJ INTO THIS ACTIVITY ALSO
FAVORS ONE OR MORE MCS-TYPE COMPLEXES AS CONVECTION CONSOLIDATES AND
BECOMES ELEVATED AFTER DARK OVER THE CNTRL PLAINS.  ISOLATED
TORNADOES SEEM POSSIBLE EARLY IN STORM EVOLUTION...THEN DAMAGING
WINDS AND HAIL WITH THE LARGER CLUSTERS.

...SWRN U.S...

PRECIPITABLE WATER VALUES REMAIN SEASONABLY HIGH ACROSS AZ INTO SRN
CA...WITH VALUES WELL IN EXCESS OF 1 IN NEAR THE BORDER.  LARGE
SCALE FLOW REGIME HAS YET TO CHANGE AND THIS SHOULD RESULT IN
ANOTHER CONVECTIVELY ACTIVE DAY ACROSS THIS REGION.  SLIGHT RISK MAY
NEED TO BE ADDED IN LATER OUTLOOKS TO ADDRESS THE POSSIBILITY FOR
WWD PROPAGATING ORGANIZED THUNDERSTORMS ACROSS THE DESERTS.

..DARROW.. 07/19/2006