[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 041621
SWODY1
SPC AC 041619

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1119 AM CDT TUE APR 04 2006

VALID 041630Z - 051200Z

...THERE IS A SLGT RISK OF SVR TSTMS CENTRAL AND SOUTHERN
CALIFORNIA...

...SYNOPSIS...
WHILE DEEP UPPER LOW DEVELOPS OVER NEW ENGLAND...THE STRONG COLD LOW
OFF CA COAST WILL BE MOVING INLAND TONIGHT. TRANSITORY RIDGE 
SURFACE AND ALOFT WILL SHIFT EWD ACROSS THE PLAINS ALLOWING GULF
MOISTURE TO RETURN NORTHWARD THRU THE SRN/CENTRAL PLAINS.

...CA...
THE COLD AND CONVECTIVELY ACTIVE UPPER LOW OFF CA COAST WILL MOVE
INLAND TONIGHT.  LAPSE RATES AROUND 7C/KM AND POTENTIAL MLCAPES TO
AROUND 500 J/KG COUPLED WITH LARGE SCALE ASCENT AHEAD OF THE UPPER
SYSTEM SUPPORT THE POTENTIAL OF A FEW SEVERE THUNDERSTORMS
DEVELOPING THIS AFTERNOON FROM THE CENTRAL CA COAST INLAND ACROSS
THE SAN JOAQUIN AND SRN SACRAMENTO VALLEYS.

WHILE THE FLOW IS QUITE MERIDIONAL AHEAD OF THE UPPER SYSTEM...20KTS
OF SFC-1KM SHEAR IN CONCERT WITH THE BACKED BOUNDARY LAYER FLOW 
WILL SUPPORT POTENTIAL FOR ORGANIZED LOW TOPPED THUNDERSTORMS. 
SUPERCELLS WOULD ALSO BE POSSIBLE PARTICULARLY NRN SAN JOAQUIN
VALLEY WWD TO COAST PROVIDED THERE IS SUFFICIENT HEATING TO REALIZE
THE POTENTIAL INSTABILITY.  THUS IN ADDITION TO HAIL AND LOCALIZED
STRONG DAMAGING WINDS...ISOLATED FUNNELS AND TORNADOES WOULD ALSO BE
 EXPECTED ALONG WITH WATERSPOUTS ALONG THE CENTRAL CA COAST.

OVERNIGHT SHEAR PROFILES AND LAPSE RATES IMPROVE CONSIDERABLY SWD
INTO THE LA BASIN AS 130KT UPPER JET MAX MOVES ONSHORE SRN CA AFTER
06Z.  WHILE MLCAPES WILL GENERALLY BE LESS THAN 300 J/KG...TERRAIN
INDUCED BACKING WIND PROFILES AND STRONG ASCENT WITH PASSAGE OF
VIGOROUS UPPER TROUGH...LOW TOPPED SUPERCELLS ARE CERTAINLY A
POSSIBILITY.  IN ADDITION TO BRIEF DAMAGING WINDS/HAIL...ISOLATED
TORNADOES/WATERSPOUTS WOULD ALSO BE A POSSIBILITY AT LEAST AS FAR S
AS ORANGE COUNTY.

...CENTRAL FL...
WILL MAINTAIN A LOW PROBABILITY OF THUNDERSTORMS AHEAD OF THE
FRONTAL ZONE MOVING SLOWLY SWD THRU CENTRAL FL.  MOST MODEL GUIDANCE
INDICATE THAT THE STRONG HEATING S OF FRONT ALONG WITH AVAILABLE
MOISTURE WILL BE SUFFICIENT TO OVERCOME THE CURRENT CINH WITH A
COUPLE OF STRONG/SEVERE STORMS BY MID AFTERNOON.  WITH LAPSE RATES
AROUND 7C/KM AND MLCAPES AHEAD OF FRONT TO 1500 J/KG ISOLATED LARGE
HAIL/DOWNBURST WINDS ARE POSSIBLE WITH THESE STORMS UNTIL AROUND
SUNSET.

...SRN KS/NRN OK INTO SWRN MO/WRN AR...
WITH THE LOW LEVEL JET STRENGTHENING TONIGHT ACROSS SRN
PLAINS...ELEVATED MOISTURE AND INSTABILITY WILL SPREAD NEWD TOWARD
LOWER MO VALLEY.  STEEP MID LEVEL LAPSE RATES COUPLED WITH RETURNING
GULF MOISTURE LEAD TO POTENTIAL OF ELEVATED CAPES TO 750 J/KG. IN
ADDITION FORECAST SOUNDINGS 40-50 KT OF CLOUD LAYER SHEAR WOULD LEAD
TO MID LEVEL ROTATION IN THUNDERSTORMS THAT DEVELOP IN THE WARM
ADVECTION REGIME.  LARGE HAIL WOULD BE POSSIBLE ASSOCIATED WITH ANY
OF THESE STORMS...WHICH WOULD MOST LIKELY OCCUR AFTER 06Z.

..HALES/TAYLOR.. 04/04/2006