[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 191633
SWODY1
SPC AC 191632

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1132 AM CDT FRI MAY 19 2006

VALID 191630Z - 201200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE LOWER MO
RIVER VALLEY INTO THE TN RIVER VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN
INTERMOUNTAIN WEST...

...LOWER MO RIVER VALLEY INTO THE TN VALLEY...
SURFACE ANALYSES INDICATE OUTFLOW BOUNDARY/STATIONARY FRONT
EXTENDING SE-NW FROM THE MID SOUTH INTO CENTRAL/ERN MO.  MORNING
CONVECTION APPEARS TO BE TIED TO WEAK SHORTWAVE TROUGH NOW MOVING
ACROSS THE LOWER OH RIVER VALLEY.  WITH PERSISTENT SURFACE HEATING
AHEAD OF THESE STORMS...ACTIVITY MAY INCREASE AND BECOME MARGINALLY
SEVERE INTO WRN TN/NERN MS/NRN AL THIS AFTERNOON ONCE CAP WEAKENS. 
HOWEVER...MORE VIGOROUS ACTIVITY SHOULD DEVELOP AHEAD OF UPSTREAM
SHORTWAVE TROUGH NOW MOVING SEWD ACROSS THE DAKOTAS.  MODELS
CONTINUE TO DRASTICALLY INCREASE SURFACE DEW POINTS AHEAD OF
ADVANCING SURFACE COLD FRONT ASSOCIATED WITH APPROACHING SYSTEM. 
EXPECT NON-ADVECTIVE PROCESSES WILL ALLOW SOME INCREASE IN SURFACE
DEW POINTS THROUGH THE AFTERNOON INTO SRN MO/NRN AR WITH DEW POINTS
AROUND 60F POSSIBLE ACROSS THIS REGION.  MODIFIED FORECAST SOUNDINGS
INDICATE HEATING WILL SUPPORT MARGINAL TO MODERATE INSTABILITY WITH
MLCAPES AROUND 1O00 J/KG LATE TODAY...WITH RATHER STRONG DEEP LAYER
SHEAR UNDER NWLY FLOW ALOFT.  EXPECT DEVELOPMENT WILL OCCUR BETWEEN
21-00Z NEAR TRIPLE POINT SURFACE LOW OVER MO AND POSSIBLY ALONG
OUTFLOW BOUNDARY/WARM FRONT INTO THE LOWER OH RIVER VALLEY.  WLY LLJ
WILL BE SUSTAINED/INCREASE ACROSS THE MID SOUTH LATER TODAY AND THIS
EVENING SUGGESTING ACTIVITY WILL INCREASE/SPREAD ESEWD INTO THE
EARLY NIGHTTIME HOURS. DAMAGING WINDS AND LARGE HAIL WILL BE
PRIMARY SEVERE THREATS.

...NRN INTERMOUNTAIN REGION INTO PORTIONS OF THE PAC NW...
SLY FLOW ALOFT WILL STRENGTHEN ACROSS THIS REGION AHEAD OF SHORTWAVE
TROUGH NOW APPROACHING THE PAC NW COAST.  SURFACE DEW POINTS REMAIN
IN THE LOWER 50S ALONG AND EAST OF THE CASCADES...SUGGESTING
MODERATE INSTABILITY WILL DEVELOP OVER LOWER ELEVATIONS TODAY GIVEN
RELATIVELY STEEP LAPSE RATES IN PLACE. DEVELOPMENT SHOULD INCREASE
ALONG AND NEAR HIGHER TERRAIN FROM FAR NRN CA INTO CENTRAL ORE/WA BY
21Z...WITH STORMS PERSISTING AND STRENGTHENING AS THEY ENCOUNTER
MODERATE INSTABILITY THROUGH THE EARLY EVENING.  FORECAST SOUNDINGS
INDICATE DEEP LAYER SHEAR SUFFICIENT FOR ORGANIZED LINES/SUPERCELLS
WHICH WILL INCREASE THE THREAT OF LARGE HAIL/DAMAGING WINDS. 
TORNADO THREAT SHOULD BE MITIGATED BY RELATIVELY WEAK LOW LEVEL
SHEAR FORECAST.

...COASTAL NEW ENGLAND...
DEEP UPPER LOW IS SUSTAINING STRONG...FAST MOVING STORMS NOW
APPROACHING THE ME COAST ALONG NWRN EDGE OF MARGINAL SBCAPE AXIS. 
SHEAR AND DEEP ASCENT REMAIN QUITE STRONG AND MAY ALLOW BRIEF SEVERE
WIND GUSTS WITH THESE LINES AS THEY MOVE INLAND.  FURTHER
DEVELOPMENT MAY OCCUR DURING THE AFTERNOON AND ALSO LIFT QUICKLY NWD
ALONG THE NEW ENGLAND COAST.  FROM THE LOWER HUDSON INTO THE CT
RIVER VALLEYS...ISOLATED HAIL...SOME NEAR SEVERE LIMITS...MAY
ACCOMPANY STRONGER CELLS DEVELOPING IN CLOSER PROXIMITY TO UPPER
LEVEL LOW/MID LEVEL COLD POCKET NOW MOVING INTO THE NERN U.S.

..EVANS/GUYER.. 05/19/2006