MESOSCALE PRECIPITATION DISCUSSION 0351
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
614 PM EDT SUN SEP 07 2014
 
AREAS AFFECTED...SOUTHERN CA...NORTHWESTERN AZ...SOUTHERN
NV...SOUTHERN UT 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 072201Z - 080301Z
 
SUMMARY...ENHANCED MONSOON CONDITIONS ARE EXPECTED INTO THIS
EVENING DUE TO MUCH ABOVE NORMAL MOISTURE VALUES ACROSS THE
REGION.  RAINFALL RATES OF UP TO 2-INCHES AN HOUR MAY CAUSE FLASH
FLOODING.

DISCUSSION...SCATTERED THUNDERSTORMS HAVE CONTINUED TO DEVELOP
THIS AFTERNOON ALONG THE MOUNTAINS OF INTERIOR SOUTHERNMOST CA AND
ALONG THE HIGH TERRAIN ACROSS NORTHWESTERN AZ INTO SOUTHERN NV AND
SOUTHERN UT. THE ATMOSPHERE REMAINS QUITE MOIST ACROSS THE REGION
AS MOISTURE ALOFT FROM TROPICAL STORM NORBERT FORTIFIES MONSOONAL
MOISTURE MOVING NORTH FROM THE GULF OF CA INTO THE LOWER CO BASIN.
 LATEST MESOANALYSIS SHOWS PRECIPITABLE WATER VALUES AT OR ABOVE
2-INCHES CENTERING NEAR THE CA/AZ BORDER -- VALUES THAT ARE WELL
ABOVE NORMAL FOR EARLY SEPTEMBER.  MIXED LAYER CAPE VALUES OF
1000-2000+ J/KG ARE SHOWN ACROSS MUCH OF THE HIGHLIGHTED REGION. 
MEANWHILE MEAN 850-700 HPA INFLOW OF 15-20 KTS ARE HELPING TO
SPREAD MOISTURE NORTHWARD ACROSS THE REGION.

AS AN UPPER TROUGH SLOWLY DIGS INTO NORTHERN CA...THIS INFLOW IS
EXPECTED TO SUSTAIN ITSELF INTO THE EVENING HOURS LEVEL...WHICH IN
TURN SHOULD SUPPORT THE HIGH MOISTURE VALUES.  THE LATEST RAP
SHOWS INSTABILITY REMAINING SUFFICIENTLY HIGH OVER THE NEXT FEW
HOURS BEFORE GRADUALLY DIMINISHING AFTER SUNSET.  DUE TO THE
EXISTING MOISTURE...HOURLY RAIN RATES UP TO 2-INCHES AN HOUR ARE
POSSIBLE.  THESE RATES COULD LEAD TO FLASH FLOODING/DEBRIS FLOWS.

PEREIRA

ATTN...WFO...FGZ...PSR...SGX...SLC...VEF...

ATTN...RFC...CBRFC...CNRFC...

LAT...LON   38351168 37871129 36861183 35291160 34701231 
            34871356 34961462 34211466 33981495 34181550 
            33811601 33761632 33351620 32741610 32501608 
            32721662 33401682 33841701 34321739 34891742 
            34831627 35221590 36101596 36541578 37571430 
            38171283