[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 150558
SWODY1
SPC AC 150556

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1256 AM CDT THU JUN 15 2006

VALID 151200Z - 161200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE CNTRL AND NRN
PLAINS INTO THE UPPER MS VALLEY...

...SYNOPSIS...

LARGE SCALE PATTERN WILL REMAIN DOMINATED BY AN UPPER TROUGH OVER
THE WRN THIRD OF THE COUNTRY...AN UPPER RIDGE OVER THE MS VALLEY
AREA AND AN UPPER TROUGH OVER THE ERN THIRD. A SERIES OF SHORTWAVE
TROUGHS WILL MOVE THROUGH THE WRN U.S. UPPER TROUGH INCLUDING ONE
THAT WILL CONTINUE NEWD THROUGH THE NRN PLAINS THURSDAY. A COLD
FRONT WILL ACCOMPANY THIS FEATURE INTO THE ERN DAKOTAS WHILE A WARM
FRONT LIFTS NEWD THROUGH THE UPPER MS VALLEY. A SECONDARY IMPULSE
WILL EJECT INTO THE CNTRL HIGH PLAINS THURSDAY AFTERNOON AND
EVENING.

...NERN CO...NWRN KS...WRN AND CNTRL NEB AND ERN SD...

A RESERVOIR OF WARM MID LEVEL AIR ASSOCIATED WITH THE EML 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 MUCH OF THE DAY. BOUNDARY LAYER DEWPOINTS IN
THE UPPER 40S TO LOWER 50S WILL CHARACTERIZE THE HIGH PLAINS WARM
SECTOR. N OF THE WARM FRONT ACROSS PARTS OF ND INTO THE UPPER MS
VALLEY...DEWPOINTS IN THE LOWER 60S MAY PERSIST. STRONG SURFACE
HEATING AND STEEP LAPSE RATES WILL CONTRIBUTE TO MLCAPE AROUND 1500
TO 2000 J/KG IN THE 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 POTENTIAL FOR SOME STORMS
TO DEVELOP SUPERCELL STRUCTURES WITH LARGE HAIL AND DAMAGING WIND
THE MAIN THREATS. ACTIVITY MAY CONSOLIDATE INTO ONE OR MORE MCSS AS
IT SPREADS NEWD. CAP WILL BE STRONGER WITH EWD EXTENT INTO THE
PLAINS AND WILL LIKELY INCREASE DURING THE EVENING.
HOWEVER...STRENGTHENING LOW LEVEL JET WILL RESULT IN STRONG STORM
RELATIVE INFLOW AND MAY RESULT IN SUFFICIENT LIFT FOR STORMS TO
PERSIST THROUGH THE EVENING...BUT ACTIVITY MAY BECOME INCREASINGLY
ELEVATED OVERNIGHT.


... ERN ND THROUGH NWRN MN...

LEFTOVER CONVECTIVE DEBRIS COULD SLOW HEATING IN THIS AREA...BUT THE
POTENTIAL FOR MODERATE INSTABILITY WILL EXIST AHEAD OF THE COLD
FRONT AS THE BOUNDARY LAYER WARMS DURING THE AFTERNOON. STORMS ARE
EXPECTED TO INTENSIFY IN VICINITY OF THE COLD FRONT AND POSSIBLY IN
ZONE OF WARM ADVECTION AND LIFT N OF RETREATING WARM FRONT. OVERALL
THREAT IN THIS AREA COULD BE LIMITED BY WEAK FLOW THROUGH THE LOWEST
3 KM...BUT STEEP LAPSE RATES AND MODERATE VERTICAL SHEAR THROUGH A
DEEPER LAYER COULD SUPPORT SOME ORGANIZED STORM STRUCTURES. LARGE
HAIL AND DAMAGING WIND WILL BE THE MAIN THREATS THROUGH EARLY
EVENING.

..DIAL/GUYER.. 06/15/2006