[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 060609
SWODY2
SPC AC 060608

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0108 AM CDT TUE JUN 06 2006

VALID 071200Z - 081200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OH VALLEY TO MIDDLE
TN...

...THERE IS A SLGT RISK OF SVR TSTMS OVER A LARGE PART OF THE
INTERIOR NORTHWEST/NRN ROCKIES/NRN HIGH PLAINS...

...SYNOPSIS...
EXPANSIVE WCNTRL U.S. UPPER RIDGE IS FORECAST TO BEGIN TO BREAK DOWN
ACROSS THE NRN ROCKIES AND NRN PLAINS THROUGH WEDNESDAY AS NUMEROUS
SHORT WAVE IMPULSES RIDE AROUND THE WRN/NRN PERIPHERY OF THE
ANTICYCLONE AND COMBINE WITH STRONGER HEIGHT FALLS ACCOMPANYING A
PACIFIC SHORT WAVE TROUGH MOVING INLAND OVER WA/ORE THROUGH EARLY
THURSDAY. A DEAMPLIFYING SHORT WAVE IMPULSE... CURRENTLY CROSSING
THE UPPER MS VALLEY ON THE ERN FLANK OF THE LARGE UPPER HIGH...IS
FORECAST TO SPREAD SEWD FROM THE GREAT LAKES TO THE OH VALLEY
THROUGH WEDNESDAY EVENING. THIS SYSTEM WILL ACT TO REESTABLISH THE
MEAN TROUGH SITUATED ACROSS THE ERN SEABOARD AS EXISTING/PERSISTENT
DEEP LAYER LOW OVER THIS REGION IS EJECTED NEWD OFF THE NEW ENGLAND
COAST THROUGH EARLY THURSDAY.

...MIDWEST TO LOWER MS VALLEY/NRN GULF COAST...
INCREASINGLY DIFFLUENT MID LEVEL FLOW WILL DEVELOP ACROSS THE
MIDWEST AND LOWER MS VALLEY THROUGH WEDNESDAY AFTERNOON AS WEAK
HEIGHT FALLS ASSOCIATED WITH GREAT LAKES/MIDWEST SHORT WAVE TROUGH
SPREAD SEWD ON THE ERN FLANK OF THE LARGE UPPER RIDGE. LOW LEVEL
MOISTURE FOCUSED ALONG WEAK WIND SHIFT WILL COMBINE WITH SURFACE
HEATING TO PRODUCE A NARROW AXIS OF STRONGER INSTABILITY FROM LA/AR
NEWD TO IND/OH. STRONGER LARGE SCALE FORCING FOR ASCENT ASSOCIATED
WITH THE SHORT WAVE TROUGH IS FORECAST TO EXIST ACROSS THE OH VALLEY
AREA...COINCIDENT WITH MAXIMUM IN DIURNAL DESTABILIZATION.
ADDITIONALLY...STRONGER MID LEVEL NWLY FLOW WILL CONTRIBUTE TO MORE
THAN ADEQUATE SHEAR ACROSS THIS REGION FOR ORGANIZED STORMS.
ACTIVITY MAY BUILD/INCREASE SWWD INTO INSTABILITY AXIS FROM SRN IND
ACROSS KY AND MIDDLE TN AS MID LEVEL WIND MAX PASSES OVERHEAD. A FEW
CLUSTERS OF ORGANIZED STORMS...PERHAPS A COUPLE OF SUPERCELLS...WITH
HAIL AND WIND DAMAGE POTENTIAL APPEAR POSSIBLE.

ACTIVITY FARTHER SWWD INTO THE LOWER MS VALLEY/NRN GULF COAST IS
FORECAST TO REMAIN MORE ISOLATED GIVEN WEAKER LARGE SCALE SUPPORT.

...INTERIOR NORTHWEST ACROSS THE ROCKIES TO NRN PLAINS...
WIDESPREAD CONVECTION IS FORECAST ACROSS PARTS OF THE GREAT BASIN AS
DIURNAL HEATING COMBINES WITH A NUMBER OF SMALL SCALE PERTURBATIONS
RIDING UP AND AROUND THE WRN/NRN FLANK OF THE UPPER RIDGE.
ADDITIONAL ACTIVITY IS EXPECTED TO INCREASE EAST OF THE CONTINENTAL
DIVIDE FROM NM ACROSS CO/WY/MT OWING TO RELATIVELY MOIST UPSLOPE
FLOW IN VICINITY OF RESIDUAL FRONTAL BOUNDARY BACKED INTO THE HIGHER
TERRAIN.

MODELS APPEAR IN REASONABLE AGREEMENT THAT STRONGEST LARGE SCALE
FORCING WILL DEVELOP EAST ACROSS THE CASCADES AS A PACIFIC SHORT
WAVE TROUGH MOVES INLAND AND PROMOTES ANOTHER AREA OF STRONG TO
SEVERE CONVECTIVE POTENTIAL FROM THE UPPER COLUMBIA RIVER
VALLEY...EAST ACROSS WRN MT.

OVERALL FORCING AND DEEP LAYER SHEAR WILL FAVOR SEVERE STORMS WITH
HAIL AND WIND OVER ALL OF THESE AREAS WITH MORE PERSISTENT ACTIVITY
PERHAPS CONSOLIDATING NEAR THE SHORT WAVE TROUGH FROM ORE/WA EWD
ACROSS MT DURING THE AFTERNOON AND EVENING.

OTHER STORMS/SUPERCELLS DEVELOPING ACROSS THE HIGHER TERRAIN AND
ADJACENT PLAINS FROM NRN WY AND SERN MT TO THE SD BLACK HILLS ARE
EXPECTED TO CONGEAL INTO AN MCS OR TWO THROUGH THE EVENING. IN
ADDITION TO ISOLATED TORNADO THREAT WITH INITIAL DISCRETE
CONVECTION...LARGE HAIL AND WIND POTENTIAL MAY PERSIST AS ACTIVITY
DEVELOPS INTO STRENGTHENING WARM AIR ADVECTION REGIME FROM ERN MT
INTO THE WRN DAKOTAS OVERNIGHT.

...SOUTHWEST...
ANTICIPATED PLUME OF GREATER MID LEVEL MOISTURE STREAMING NWD ON THE
WRN FLANK OF THE UPPER RIDGE...COUPLED WITH STRONG HEATING AND
UPSLOPE FLOW ACROSS THE SOUTHWEST...WILL LIKELY SPUR SCATTERED TO
NUMEROUS TSTMS. MODELS SUGGEST THAT SLIGHTLY STRONGER MID LEVEL FLOW
ACROSS SRN AZ WILL CONTRIBUTE TO POCKETS OF GREATER DEEP LAYER SHEAR
SUPPORTIVE OF UPDRAFT PERSISTENCE. ISOLATED TO WIDELY SCATTERED
DAMAGING DOWNBURSTS...AND A FEW HAIL EVENTS...APPEAR POSSIBLE WITH
THIS ACTIVITY THROUGH EVENING.

..CARBIN.. 06/06/2006