[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 261601
SWODY1
SPC AC 261559

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1059 AM CDT MON JUN 26 2006

VALID 261630Z - 271200Z

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF THE NRN PLAINS...

...THERE IS A SLGT RISK OF SVR TSTMS IL/IND INTO WRN KY/NWRN TN...

...NRN PLAINS...
WV IMAGERY INDICATES POTENT VORT CENTER/SHORTWAVE TROUGH DIGGING
SEWD ACROSS THE SRN CANADIAN PRAIRIES...WITH ASSOCIATED SURFACE COLD
FRONT NOW PUSHING INTO NERN ND/FAR NWRN MN.  SURFACE DEW POINTS ARE
EXPECTED TO HOLD IN THE MID TO UPPER 50S F ACROSS NRN MN INTO SERN
ND AHEAD OF THIS SYSTEM...WITH MLCAPE FORECAST TO INCREASE INTO THE
1000-1500 J/KG RANGE AS AFTERNOON TEMPERATURES RISE THROUGH THE MID
70S.  STEEP LOW AND MID TROPOSPHERIC LAPSE RATES UNDER -16C TO -20C
H5 TEMPERATURES SHOULD FOSTER A RISK OF LARGE HAIL AND DAMAGING
WINDS AS STORMS INCREASE IN COVERAGE/INTENSITY THROUGH THE DAY.  LOW
AND DEEP LAYER SHEAR APPEAR WEAK FOR SUPERCELLS...THOUGH SFC-6 KM
SHEAR FROM 20-25 KT WILL REMAIN SUPPORTIVE OF ORGANIZATION INTO
CLUSTERS/LINES SPREADING QUICKLY SSEWD INTO THE EARLY EVENING. 
SEVERE THREAT EXPECTED TO DIMINISH QUICKLY AFTER SUNSET.

...IL/IND INTO WRN TN...
SLOW MOVING MID/UPPER LEVEL TROUGH WILL AGAIN FOCUS THUNDERSTORM
DEVELOPMENT OVER MUCH OF THIS REGION TODAY...ESPECIALLY NEAR COLDER
MID LEVEL AIR EXPECTED TO OVERSPREAD PORTIONS OF IL/IND AND THE
LOWER OH RIVER VALLEY. WEAK SURFACE LOW ASSOCIATED WITH THIS SYSTEM
WAS LOCATED NEAR MTO THIS MORNING WITH BROAD SURFACE CONVERGENCE
AXES EXTENDING NNWWD ACROSS CENTRAL IL AND SSWWD INTO THE LOWER MS
RIVER VALLEY.  THESE FEATURES WILL LIKELY MOVE VERY LITTLE THROUGH
THE DAY AND ARE EXPECTED TO FOCUS SCATTERED THUNDERSTORMS AS AIR
MASS BECOMES MARGINALLY TO MODERATELY UNSTABLE AND WEAKLY CAPPED BY
THE MID AFTERNOON.  PRIMARY REGION WILL LIKELY OCCUR WITHIN STRONGER
ASCENT AND COOLER AIR ALOFT/STEEPER LAPSE RATES WITHIN RIGHT EXIT
REGION OF MID/UPPER LEVEL JET NOSING ACROSS THE MID SOUTH THIS
MORNING.  A FEW STORMS WILL BE CAPABLE OF LARGE HAIL...WITH
ADDITIONAL CHANCE OF A LAND SPOUT TORNADO OR TWO WHERE LOW LEVEL
CAPE AND SURFACE VORTICITY ARE MAXIMIZED NEAR SURFACE LOW/INVERTED
TROUGH AXIS.

...CAROLINAS TO MID ATLANTIC STATES...
DEEP...VERY MOIST UNIDIRECTIONAL SLY FLOW WILL REMAIN CONDUCIVE FOR
QUASI-STATIONARY BANDS OF BACK-BUILDING CONVECTION/STORMS TODAY
THROUGH TUESDAY FROM THE CAROLINAS N INTO PA/NJ/NY.  THE MOST
SERIOUS THREAT POSED WILL BE FLOODING...BUT A LOW PROBABILITY WILL
ALSO EXIST FOR TORNADOES.  THIS POTENTIAL WILL BE GREATEST BOTH
ALONG A  WARM FRONT NOW EXTENDING FROM S SCNTRL PA/CNTRL MD SSWWD
INTO THE VA/NC PIEDMONT...AND ALONG WARM SECTOR CONVECTIVE BANDS
DEVELOPING WITH SFC HEATING.  WHILE ANY SUCH THREAT SHOULD BE MAINLY
DIURNAL...EXPECTED STRENGTHENING OF 925-850 MB FLOW THIS EVENING
FROM VA NWD INTO MD/PA SUGGESTS THAT A LIMITED POTENTIAL MAY PERSIST
INTO THE NIGHT.  FARTHER S...THE THREAT MAY ALSO INCREASE LATE IN
THE PERIOD ALONG THE SC/SRN NC CSTL PLN AS LOW LEVEL
FLOW/DIRECTIONAL SHEAR STRENGTHEN DOWNSTREAM FROM APPROACHING
BAHAMAS DISTURBANCE.

...ERN/AZ/NM/SRN CO...
WEAK N/NELY MID LEVEL FLOW ON FRINGE OF GRT BASIN UPR RIDGE WILL
FAVOR S/SW PROPAGATION OF CONVECTION FORMING OVER THE HIGHER TERRAIN
OF NM/ERN AZ LATER TODAY.  BOUNDARY LAYER MOISTURE HAS INCREASED
SOMEWHAT RELATIVE TO RECENT DAYS AND THUS CONVECTIVE COVERAGE MAY
CONTINUE TO INCREASE.  SOME OF THE STORMS MAY YIELD STRONG OUTFLOW
WINDS AND PERHAPS MARGINALLY SEVERE HAIL AS THE GUST FRONTS MOVE
ACROSS THE LWR DESERTS.  BUT DEGREE OF INSTABILITY AND EXPECTED
STORM ORGANIZATION APPEAR TOO LIMITED ATTM TO WARRANT A SLIGHT RISK.

..EVANS/GUYER/CORFIDI.. 06/26/2006