[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 131826
SWOMCD
SPC MCD 131825 
AZZ000-NVZ000-CAZ000-132130-

MESOSCALE DISCUSSION 1991
NWS STORM PREDICTION CENTER NORMAN OK
0125 PM CDT FRI AUG 13 2004

AREAS AFFECTED...SRN CA...SRN/WRN AZ AND FAR SRN NV

CONCERNING...SEVERE THUNDERSTORM POTENTIAL...HEAVY RAINFALL 

VALID 131825Z - 132130Z

ISOLATED DAMAGING WINDS GUSTS AND MARGINALLY SEVERE HAIL WILL BE
POSSIBLE WITH THE STRONGEST STORMS OVER THE REGION THROUGH THE
AFTERNOON. HOWEVER...THE GREATER THREAT WITH THE STORMS SHOULD BE
HEAVY RAINFALL.

SATELLITE IMAGERY INDICATED SEVERAL WEAK VORT CENTERS MOVING SLOWLY
ENEWD OVER THE LOWER COLORADO RIVER VALLEY/MOJAVE DESERT. A VERY
MOIST AIRMASS WAS IN PLACE WITH MID 60S DEWPTS AS FAR NORTH AS
NEEDLES AND THE COACHELLA VALLEY. REMNANT CONVECTIVE BOUNDARY FROM
YESTERDAY STORMS WILL CONTINUE TO ORGANIZE CONVECTION ACROSS FAR
SERN CA INTO FAR SWRN AZ. ADDITIONAL STORMS WILL DEVELOP IN THE
UPSLOPE FLOW OVER THE MTNS OF SRN CA INTO FAR SRN NV AND WRN AZ. A
DEEPLY MIXED BOUNDARY LAYER WITH 30-40 DEG TEMPERATURE DEWPT SPREADS
AT THE SFC WILL SUPPORT STRONG WINDS. IN HIGHER ELEVATIONS WHERE
LESS MELTING WILL OCCUR...ISOLATED MARGINALLY SEVERE HAIL WILL BE
POSSIBLE. 

HOWEVER...THE GREATER THREAT APPEARS TO BE HEAVY RAINFALL DUE TO
HIGH PRECIPITABLE WATER VALUES EVIDENT ON THE 18Z NKX AND DRA
SOUNDINGS ALONG SLOW STORM MOTIONS OF 10 KTS OR LESS. WEAK WIND
FIELDS...ALONG WITH FAVORABLE LOW LEVEL SELY UPSLOPE FLOW INTO THE
LEE SIDE OF THE COASTAL RANGE MTNS OF SRN CA AND SLY FLOW INTO THE
MTNS OF WRN AZ WILL ALLOW FOR CONVECTIVE TRAINING/BACKBUILDING
ENHANCING RAINFALL RATES UP TO AND ABOVE 1 INCH/HR GIVEN SLOW STORM
MOTIONS ANTICIPATED.

..CROSBIE.. 08/13/2004

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

ATTN...WFO...TWC...FGZ...PSR...VEF...SGX...

32681481 32661646 33611681 34231737 35181677 36031580
36181468 33521165 32001165 32451334 

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