[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 211010
SWOMCD
SPC MCD 211010 
CAZ000-211315-

MESOSCALE DISCUSSION 0186
NWS STORM PREDICTION CENTER NORMAN OK
0410 AM CST MON FEB 21 2005

AREAS AFFECTED...COASTAL SRN CA INCLUDING WINDWARD MOUNTAIN SLOPES

CONCERNING...HEAVY RAINFALL 

VALID 211010Z - 211315Z

PLUME OF MDT AND EMBEDDED HEAVY PRECIP WILL CONTINUE ACROSS ERN
ORANGE AND SWRN SAN BERNARDINO COUNTIES AND SPREAD INLAND PORTIONS
WRN SAN DIEGO AND EXTREME WRN RIVERSIDE COUNTIES.  RAIN RATES
COMMONLY AROUND 1-1.5 INCH/HOUR ARE LIKELY IN MOST AREAS WITH LOCAL
RATES NEAR 2 INCHES/HOUR OVER WINDWARD SLOPES OF COASTAL
HILLS/MOUNTAINS WHERE OROGRAPHIC ASCENT IS MAXIMIZED.

STRONG LOW LEVEL WAA PROFILE INDICATED IN VWP FROM NKX...INCLUDING
DEEP 30-40 KT LLJ THAT WILL MAXIMIZE LIFT AND RAINFALL OVER STEEPEST
FACING SLOPES. MODIFIED 00Z NKX RAOB AND RUC SOUNDINGS INDICATE
NEARLY SATURATED ENVIRONMENT THROUGH MOST OF
TROPOSPHERE...CHARACTERIZED BY .75-1 INCH PW.  ALSO...MUCAPES
100-200 J/KG NEAR COASTLINE WILL SUPPORT LOCALIZED CONVECTIVE
ENHANCEMENT TO RAIN RATES...INCLUDING A FEW TSTMS. 
ACCORDINGLY...SEVERAL CG LTG STRIKES HAVE BEEN INDICATED S OF SAN
CLEMENT ISLAND AND W SAN DURING PAST 1-2 HOURS...IN OFFSHORE PORTION
OF PRECIP PLUME.  AS BAROCLINIC BAND ASSOCIATED WITH OFFSHORE
DEEP-LAYER CYCLONE SHIFTS EWD...SO WILL PRECIP PLUME...CAUSING
THREATS ASSOCIATED WITH HEAVY RAINS TO COVER MORE OF REGION FROM SAN
NWD OVER WRN RIVERSIDE COUNTY.

VWP HODOGRAPH INDICATES FAVORABLE LOW LEVEL SHEAR PROFILES FOR
LOW-TOP SUPERCELLS...GIVEN SHAPE/DEPTH OF RUC-DERIVED CAPE PROFILES.
 SRH IN 0-1 KM IS OVER 200 J/KG GIVEN RIGHT-MOVING CELL. 
HOWEVER...WHILE NOT ZERO...TORNADO PROBABILITIES APPEAR LOWER THAN
TWO MORNINGS AGO BECAUSE OF LESS FAVORABLE CONVECTIVE MODE FOR
SUSTAINED STORM SCALE ROTATION -- EMBEDDED INSTEAD OF DISCRETE
CELLS.

..EDWARDS.. 02/21/2005

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...SGX...

33591789 33911772 34281757 34311716 34041687 33481683
32541688 32541714 32641785 33371797 

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