[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 151233
SWODY1
SPC AC 151231

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0731 AM CDT THU JUN 15 2006

VALID 151300Z - 161200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL HIGH PLAINS
INTO THE NRN PLAINS...

...CENTRAL/ERN ND INTO NERN SD EWD ACROSS WRN MN...
STRONG SURFACE COLD FRONT NOW PUSHING EWD ACROSS WRN ND WILL BECOME
FOCUS FOR RENEWED STRONG TO SEVERE THUNDERSTORMS BY THE MID TO LATE
AFTERNOON. CAPPING WILL LIKELY REMAIN STRONG FOR MUCH OF THE DAY AS
MORNING CONVECTIVE DEBRIS WILL BE SLOW TO DISSIPATE. 
HOWEVER....FORCED ASCENT AND STRONG AFTERNOON HEATING WITHIN LOWER
60F SURFACE DEW POINTS SHOULD ALLOW THUNDERSTORMS TO DEVELOP BY 21Z
AS AIR MASS BECOMES MODERATELY UNSTABLE.  FORECAST SOUNDINGS
INDICATE EFFECTIVE SHEAR FROM 35-40 KT SUGGESTING MORE DISCRETE
DEVELOPMENT MAY BE SUPERCELLULAR...THOUGH OVERALL EVOLUTION INTO
LINES/CLUSTERS ALONG EWD MOVING COLD FRONT IS EXPECTED THROUGH THE
EVENING.  LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE
THREATS.  HOWEVER...SURFACE LOW IS FORECAST TO DEEPEN INTO NERN
SD/SERN ND LATER THIS EVENING AND LCLS WILL REMAIN SUFFICIENTLY LOW
FOR A FEW TORNADOES.

...CENTRAL HIGH PLAINS INTO SD...
A RESERVOIR OF WARM MID LEVEL AIR ASSOCIATED WITH 17+ C TEMPERATURES
AT 700 MB WILL CONTINUE TO SPREAD EWD THROUGH THE CNTRL PLAINS. THIS
WILL SERVE TO CAP THE ATMOSPHERE TO SURFACE BASED STORMS OVER THIS
AREA FOR MUCH OF THE DAY.  DUE TO DEEP MIXING...BOUNDARY LAYER
DEWPOINTS IN THE UPPER 40S TO LOWER 50S WILL CHARACTERIZE THE HIGH
PLAINS WARM SECTOR. BOUNDARY LAYER MIXING AND INCREASING LARGE SCALE
ASCENT DOWNSTREAM FROM IMPULSE EJECTING NEWD THROUGH CO WILL
CONTRIBUTE TO THE DEVELOPMENT OF HIGH BASED STORMS OVER THE CNTRL
HIGH PLAINS. OTHER STORMS MAY DEVELOP OVER THE HIGHER TERRAIN IN
POST FRONTAL UPSLOPE REGION OF NERN CO AND SERN WY. DEEP LAYER SHEAR
FROM 40 TO 50 KT WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND
DAMAGING WIND THE MAIN THREATS.  ACTIVITY WILL LIKELY CONSOLIDATE
INTO ONE OR MORE MCSS AS IT SPREADS QUICKLY NEWD...LIKELY IN THE
FORM OF LINES/BOW ECHOES.  EXPECT AN INCREASING POTENTIAL FOR
DAMAGING WINDS...WITH ISOLATED SIGNIFICANT WIND GUSTS...AS STORMS
OVERSPREAD DEEPLY MIXED BOUNDARY LAYER AND ENHANCED CONVERGENCE
INVOF STALLED FRONT EXTENDING NNEWD ACROSS CENTRAL NEB WELL INTO THE
MID TO LATE EVENING.  ONCE CAPPING BEGINS INHIBITING STRONG SURFACE
DOWNDRAFTS OVERNIGHT...PRIMARY SEVERE THREAT WILL TRANSITION TO
LARGE HAIL AS MCS MOVES TOWARDS ERN SD/SWRN MN.

..EVANS/GUYER.. 06/15/2006