[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 171728
SWODY2
SPC AC 171728

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1228 PM CDT SAT JUN 17 2006

VALID 181200Z - 191200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
STRONG WESTERLIES WILL PERSIST IN A BELT EXTENDING FROM THE
NORTHWESTERN AND NORTH CENTRAL U.S. INTO SOUTHEASTERN CANADA THIS
FORECAST PERIOD.  A COUPLE OF WAVES EMBEDDED WITHIN THIS REGIME ARE
PROGGED TO REMAIN PROGRESSIVE...ONE ADVANCING FROM THE NORTH CENTRAL
U.S./CANADIAN BORDER AREA INTO THE GREAT LAKES REGION... AND A
SECOND MOVING INLAND ACROSS THE PACIFIC NORTHWEST INTO THE NORTHERN
INTERMOUNTAIN REGION.
  
IN ADVANCE OF THE LATTER FEATURE...AN UPPER RIDGE IS FORECAST TO
BUILD EWD INTO THE CENTRAL/SRN PLAINS WITH HEIGHT RISES ALSO
EXTENDING NWD THROUGH THE NRN HIGH PLAINS.  SHEARING OF AN UPPER
TROUGH TO THE SOUTH OF THE STRONGER WESTERLIES WILL CONTINUE ACROSS
EASTERN PORTIONS OF THE SOUTHERN PLAINS INTO THE LOWER HALF OF THE
MISSISSIPPI VALLEY...AS A SHARP UPPER RIDGE REMAINS STRONG ACROSS
THE ERN STATES.
  
...GREAT LAKES REGION SWWD TO ERN NEB/NERN KS...
AIR MASS IS PROGGED TO REMAIN VERY MOIST FROM THE WESTERN/CENTRAL
GULF STATES NORTHWARD AHEAD OF A PRE-FRONTAL TROUGH INTO THE LOWER
GREAT LAKES REGION.  AN EXTENSIVE BAND OF SHOWERS/EMBEDDED
THUNDERSTORMS SHOULD BE ONGOING AT 12Z SUNDAY ALONG THIS TROUGH FROM
PARTS OF THE LOWER MS VALLEY NNEWD INTO WI/LOWER MI.  DEEP LAYER
ASCENT AHEAD OF SHEARING UPPER TROUGH/ALONG PRE-FRONTAL TROUGH WILL
MAINTAIN THIS ACTIVITY EWD INTO THE LOWER TN/OH VALLEYS AND SRN
GREAT LAKES REGION THROUGH THE PERIOD. DESPITE STRONGER WIND FIELDS
AHEAD OF NORTH CENTRAL U.S. UPPER TROUGH... WEAK LAPSE RATES SHOULD
PRECLUDE A SEVERE THREAT WITH THIS LEAD BAND OF CONVECTION.

IN WAKE OF PRE-FRONTAL CONFLUENT ZONE...SURFACE HEATING JUST AHEAD
OF A COLD FRONT SEEMS TO SUGGEST BEST POTENTIAL/FOCUS FOR VIGOROUS
CONVECTIVE DEVELOPMENT.  THIS FRONT IS EXPECTED TO CURVE FROM THE
UPPER GREAT LAKES REGION THROUGH THE NORTH CENTRAL PLAINS BY LATE
SUNDAY AFTERNOON.  ALTHOUGH MOISTURE WILL TEND TO BE LIMITED NEAR
THIS BOUNDARY...SUFFICIENT DESTABILIZATION APPEARS LIKELY FOR AT
LEAST SCATTERED THUNDERSTORMS. ENHANCED SHEAR BENEATH STRONG
CYCLONIC MID LEVEL FLOW MAINLY OVER THE ERN EXTENT OF THE COLD FRONT
/SRN WI TO ERN IA/ MAY ALLOW A FEW STORMS TO PRODUCE HAIL/ GUSTY
WINDS APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS.  ACTIVITY
SHOULD SPREAD SOUTHEASTWARD THROUGH LOWER GREAT LAKES AND PARTS OF
THE MID MS VALLEY BEFORE DIMINISHING SUNDAY EVENING.

FARTHER WEST...MODELS SUGGEST POTENTIAL FOR ELEVATED THUNDERSTORMS
DEVELOPING SUNDAY EVENING ACROSS ERN NEB/WRN IA WITHIN INCREASING
ZONE OF LOW LEVEL WAA ALONG NOSE OF STRENGTHENING SWLY LLJ. 
ELEVATED INSTABILITY AND EFFECTIVE BULK SHEAR SUGGEST POTENTIAL FOR
A FEW STORMS TO PRODUCE HAIL...WITH ACTIVITY DEVELOPING SEWD INTO
NERN KS/NRN MO SUNDAY NIGHT.

...LOWER MS VALLEY TO EAST TX...  
SURFACE HEATING WITHIN MOIST AIR MASS /SURFACE DEWPOINTS 70+ F/ FROM
PARTS OF EAST TEXAS INTO THE LOWER MISSISSIPPI VALLEY AND BENEATH
LINGERING MID-LEVEL COOL POCKET WILL RESULT IN FAVORABLE
THERMODYNAMIC ENVIRONMENT FOR STRONG/LOCALIZED SEVERE STORMS. 
WEAKENING FLOW FIELDS SUGGEST THIS ACTIVITY SHOULD BE MORE
PULSE-TYPE WITH HAIL/GUSTY WINDS THE PRIMARY THREATS.
  
...ERN ORE/CENTRAL-SRN ID/SW MT...
FORCING/SHEAR ASSOCIATED WITH A 40-50 KT MID-LEVEL JET STREAK IS
EXPECTED TO ENHANCE CONVECTIVE POTENTIAL NEAR LOW/MID-LEVEL
BAROCLINIC ZONE ACROSS PARTS OF ERN ORE/CENTRAL AND SRN ID LATE
SUNDAY AFTERNOON/EVENING.  MOISTURE WILL BE LIMITED...BUT LAPSE
RATES WILL BECOME QUITE STEEP AND SUPPORTIVE OF AT LEAST WIDELY
SCATTERED STORMS WITH POTENTIAL FOR MICROBURSTS.

..PETERS.. 06/17/2006