[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 092005
SWODY1
SPC AC 092004

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0304 PM CDT FRI JUN 09 2006

VALID 092000Z - 101200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN
INTERMOUNTAIN WEST...

...THERE IS A SLGT RISK OF SVR TSTMS CENTRAL PLAINS REGION...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SERN PA AND NJ...

...CENTRAL PLAINS REGION...
A WEAK SURFACE LOW WAS LOCATED N CENTRAL NEB EAST OF ANW AT 19Z AND
IS FORECAST TO MOVE INTO SERN NEB BY DAYBREAK SATURDAY. A WARM FRONT
EXTENDS EWD FROM THE SURFACE LOW WITH A WEAK COLD FRONT DROPPING
SLOWLY SWD TO THE WEST OF THE LOW. BOUNDARY LAYER MOISTURE REMAINS
MEAGER...WITH DEEPER GULF MOISTURE RESTRICTED OFF THE GULF COAST.
HOWEVER...STRONG HEATING AND STEEPENING LAPSE RATES WILL LIKELY
SUPPORT MLCAPES NEAR 1000 J/KG SOUTH OF THE FRONT...THOUGH LESS
MIXED BOUNDARY LAYER NORTH OF THE FRONT SHOULD RESULT IN SLIGHTLY
HIGHER VALUES.

ISOLATED STRONG CONVECTION HAS DEVELOPED OVER THE BLACK HILLS AND
ERN WY AS LARGE SCALE FORCING HAS INCREASED IN RESPONSE TO
SHORTWAVE TROUGH LIFTING NEWD ACROSS SRN WY. THESE STORMS ARE LIKELY
TO INCREASE IN COVERAGE THROUGH THE AFTERNOON WITH A SEVERE
HAIL/WIND THREAT...REFERENCE WW 454.

CONVECTION IS ALSO EXPECTED TO DEVELOP LATER THIS AFTERNOON IN NE
NEB/SE SD/NWRN IA/SWRN MN WHERE LIFT WILL BE ACCENTUATED BY
STRENGTHENING LOW LEVEL JET OVER SURFACE BOUNDARY. THE FORECAST OF
STRONG VEERING WIND PROFILES APPEAR FAVORABLE FOR SUPERCELLS WITH
THE INITIAL CONVECTION. HOWEVER...TORNADO PROBABILITIES APPEAR LOW
DUE TO THE RELATIVELY DRY BOUNDARY LAYER AND THE STORM BASES SHOULD
BE SLIGHTLY ELEVATED. THE LOW LEVEL WARM ADVECTION SHOULD AID THE
STORMS EVOLVING INTO AN MCS TONIGHT...AND THEN SPREAD ESEWD ACROSS
IA AND INTO IL AS THE LOW LEVEL JET VEERS. THE MAIN THREAT INITIALLY
MAY BE HAIL...BUT SHOULD BECOME MORE OF A WIND THREAT AS THE
OUTFLOWS CONSOLIDATE INTO A STRONG COLD POOL.

...NRN INTERMOUNTAIN REGION...
A CLOSED MID LEVEL LOW WAS LOCATED OVER WA...WHILE EMBEDDED
SHORTWAVE TROUGHS WERE MOVING NEWD INTO STRONGER FLOW ALOFT FROM NV
NEWD INTO WRN MT. MOIST VERTICAL PROFILES WERE RESULTING IN MUCAPES
FROM 1000 TO 2000 J/KG AND WHEN COMBINED WITH 30-40 KT DEEP LAYER
SHEAR...SCATTERED SEVERE STORMS ARE EXPECTED ACROSS THE
REGION...REFERENCE WW 453 AND 455. THESE STORMS SHOULD WEAKEN TOWARD
MID EVENING AS STORM OUTFLOWS STABILIZE THE BOUNDARY LAYER.

...SERN PA AND NJ...
SCATTERED THUNDERSTORMS HAVE FORMED WITH THERMAL TROUGH ALOFT.
WEAK ASCENT WILL PROMOTE ADDITIONAL THUNDERSTORM DEVELOPMENT UNTIL
00Z...WITH A MARGINAL SEVERE HAIL/WIND THREAT IN A FEW STORMS.

...ERN NM NEWD INTO ERN CO AND WRN KS...
VERY HOT TEMPERATURES WILL RESULT IN A DEEPLY MIXED BOUNDARY LAYER
TO NEAR 550 MB. THIS SHOULD BE SUFFICIENT TO MIX PARCELS TO LFC AND
RESULT IN HIGH BASED CONVECTION. THOUGH INSTABILITY IS WEAK... THE
45-55F SURFACE TEMPERATURE/DEWPOINT SPREADS WOULD SUPPORT ISOLATED
STRONG/SEVERE WIND GUSTS WITH ANY STORMS THAT DO DEVELOP. ACTIVITY
SHOULD DIE OFF QUICKLY WITH LOSS OF DAYTIME HEATING.

..IMY.. 06/09/2006