[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 202009
SWODY1
SPC AC 202008

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0308 PM CDT TUE JUN 20 2006

VALID 202000Z - 211200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS NEW ENGLAND...

...THERE IS A SLGT RISK OF SVR TSTMS FROM CNTRL HIGH PLAINS TO SRN
WI/NRN IL...

...NEW ENGLAND...

LOOSE SQUALL LINE HAS EMERGED FROM NWRN ME...SWWD INTO CNTRL NH. 
THIS ACTIVITY IS MOVING ESEWD AT ROUGHLY 25KT AND SHOULD APPROACH
THE ME COAST BY 00Z.  THIS ACTIVITY SHOULD WEAKEN WITH LOSS OF
DAYTIME HEATING...AND/OR BE OFFSHORE BY EARLY EVENING ALONG WITH THE
ATTENDANT SEVERE THREAT.  OTHERWISE...LARGE HAIL OR LOCALIZED SEVERE
WIND GUSTS MAY CONTINUE TO ACCOMPANY THESE STORMS.  ACTIVITY WILL
REMAIN QUITE ISOLATED FARTHER SW ACROSS THE LOWER HUDSON VALLEY INTO
NERN PA/NRN NJ.

...CENTRAL PLAINS TO MID MS VALLEY REGION...

CONVECTIVE CARCASS FROM OVERNIGHT MCS HAS PROGRESSED ACROSS IA INTO
NRN IL WHERE A FEW STRONG STORMS HAVE SURVIVED ALONG LEADING
EDGE...LARGELY DRIVEN BY LOW LEVEL WARM ADVECTION.  AIRMASS ACROSS
PORTIONS OF CNTRL/SRN IL IS NOW UNCAPPED...AND MODERATELY UNSTABLE. 
IT/S NOT PARTICULARLY CLEAR WHETHER NEW UPDRAFTS CAN DEVELOP ALONG
SRN FRINGE OF OLD MCS CLOUD SHIELD...IF SO VERTICAL SHEAR IS MORE
THAN ADEQUATE FOR SUSTAINING ORGANIZED UPDRAFTS CAPABLE OF
GENERATING SOME HAIL OR GUSTY WINDS.

OF MORE CONCERN IS THE EXPECTED CONVECTIVE DEVELOPMENT ALONG
SWRN/WRN PORTIONS OF THIS CLOUD CANOPY FROM NERN KS/ERN NEB INTO
CNTRL IA.  VERY STRONG CAP REMAINS IN PLACE ACROSS THE ERN PLAINS
INTO IA.  SFC PARCELS WILL REQUIRE CONTINUED HEATING FOR CAP REMOVAL
BASED ON LATEST DIAGNOSTIC FIELDS.  VERY WARM SFC TEMPERATURES HAVE
DEVELOPED UPSTREAM ACROSS WRN/CNTRL KS WHERE READINGS ARE NOW
APPROACHING 100 F NEAR RSL.  ALTHOUGH ISOLATED SEVERE THUNDERSTORMS
ARE POSSIBLE ALONG DRY LINE DUE TO THE INTENSE SFC HEATING...LATEST
THINKING IS SUSTAINED LOW LEVEL WARM ADVECTION AND SWLY TRAJECTORIES
THROUGH 850MB WILL AGITATE ERN EDGE OF CAP ATOP RAIN COOLED BOUNDARY
LAYER OVER SWRN IA LATER THIS EVENING. SEVERE THUNDERSTORMS SHOULD
EVOLVE FROM CNTRL IA...SWWD INTO SERN NEB BY 00Z.  THIS ACTIVITY
SHOULD UPWARD EVOLVE INTO MCS CLUSTER WITH TIME EVENTUALLY SPREADING
INTO SWRN WI/NWRN IL LATER TONIGHT.

FARTHER WEST...HIGH BASED CU AND DEVELOPING THUNDERSTORMS ARE
EXPANDING IN AREAL COVERAGE FROM SERN WY INTO CNTRL CO ALONG THE
FRONT RANGE.  THIS CONVECTION SHOULD GRADUALLY INTENSIFY AS NELY LOW
LEVEL COMPONENT MAINTAINS/MOISTENS CNTRL HIGH PLAINS REGION. 
SUPERCELLS SHOULD EVOLVE INTO AN MCS OVER WRN/SWRN NEB LATE THIS
EVENING.  VERY LARGE HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE WITH
THIS ACTIVITY.

..DARROW.. 06/20/2006