[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 121722
SWODY2
SPC AC 121721

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1221 PM CDT MON JUN 12 2006

VALID 131200Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE INTERIOR PAC NW INTO
ERN MT......

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SERN
U.S......

...SYNOPTIC DISCUSSION...
LARGE SCALE FEATURES WILL MAKE ONLY SLOW EWD PROGRESS TUE. WHILE THE
CIRCULATION CENTER OF NWRN U.S. TROUGH REMAINS NEAR THE MOUTH OF THE
COLUMBIA RIVER...A STRONG MID/UPPER SPEED MAX ROTATES NEWD ACROSS
INTERMOUNTAIN REGION REACHING NRN ROCKIES BY LATER TUE NIGHT.
DOWNSTREAM RIDGE EXTENDS NWD FROM NM UPPER HIGH TO SASKATCHEWAN
SHIFTING INTO HIGH PLAINS BY 12Z WED.



...NRN INTER MOUNTAINS...NRN ROCKIES/HIGH PLAINS...

ALTHOUGH HEIGHT FALLS LATE IN THE PERIOD WILL FORCE SHARP BAROCLINIC
ZONE EWD ACROSS ID INTO WRN MT...THE TIMING OF THIS FEATURE IS NOT
PARTICULARLY CONDUCIVE FOR ENHANCING AFTERNOON CONVECTION OVER ERN
PORTIONS OF THE SLIGHT RISK.  EVEN SO...FORECAST SOUNDINGS ACROSS
THE INTERIOR NW SUGGEST THUNDERSTORMS SHOULD DEVELOP DURING THE HEAT
OF THE AFTERNOON AHEAD OF THE COLD FRONT FROM NWRN MT AT LEAST AS
FAR S AS SWRN ID.  THIS ACTIVITY WILL BE STRONGLY SHEARED.
LIMITATION...PARTICULARLY SRN ID AREA WILL BE  MOISTURE/INSTABILITY.
 ACROSS MT DEEP ELY BOUNDARY LAYER FLOW WILL PROVIDE SIGNIFICANTLY
GREATER MOISTURE AND POTENTIAL INSTABILITY. STORM MODE SRN PORTION
OF SLIGHT SHOULD BE HIGH BASED MULTI-CELLS LIMITING POTENTIAL TO
WIND DAMAGE AND MARGINAL HAIL. WITH POTENTIALLY SIGNIFICANTLY
GREATER INSTABILITY AND VEERING LOW LEVEL SHEAR ENVIRONMENT WRN
MT...SUPERCELLS WILL BE POSSIBLE.  THIS WILL ENHANCE... PARTICULARLY
LARGE HAIL THREAT WITH POSSIBLE ISOLATED TORNADOES. ACROSS THE
PLAINS OF MT WITH MORE LIMITED LOW LEVEL HEATING...SFC PARCELS MAY
REMAIN SLIGHTLY CAPPED THROUGH EARLY EVENING.  HOWEVER...APPROACHING
SPEED MAX SHOULD MAINTAIN CONVECTION ACROSS ID/WRN MT WITH ACTIVITY
POSSIBLY SPREADING ACROSS THE PLAINS OF MT DURING THE OVERNIGHT
HOURS WHERE STRONG SELY LLJ IS EXPECTED TO RESPOND TO THE
APPROACHING UPPER TROUGH.

FARTHER SOUTHEAST...THUNDERSTORM DEVELOPMENT IS POSSIBLE ALONG SFC
FRONT DRAPED FROM NERN WY INTO SWRN MN.  THIS BOUNDARY WILL PROVE
CONVERGENT AT LOW LEVELS...BUT LARGE SCALE SUBSIDENCE ALOFT BENEATH
UPPER RIDGE WILL PROVE SOMEWHAT PROBLEMATIC MAINTAINING ANY UPDRAFTS
THAT MANAGE TO BREAK CAP.  THIS ACTIVITY WILL LIKELY REMAIN ISOLATED
THROUGH EARLY EVENING...THEN POSSIBLY EXPAND IN AREAL COVERAGE AS
LLJ INCREASES AFTER DARK.  GIVEN THE EXPECTED LATE DEVELOPMENT
BENEATH UPPER RIDGE WILL MAINTAIN LOW PROBABILITIES FOR THIS
CONVECTION.

...SERN U.S...
TROPICAL AIR WILL CONTINUE SPREADING NWD AS T.S. ALBERTO HEADS
TOWARD LANDFALL NERN GULF COAST. REF NHC PRODUCTS FOR TRACK AND
LANDFALL TIMING.  FAVORABLE SHEAR WILL MAINTAIN POTENTIAL FOR
TORNADIC SUPERCELLS AHEAD OF THE TRACK OF ALBERTO.

..HALES.. 06/12/2006