MESOSCALE PRECIPITATION DISCUSSION 0229
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
413 PM EDT MON JUL 28 2014
 
AREAS AFFECTED...PORTIONS OF WESTERN UT, NV, NORTHWEST AZ, AND
EASTERN CA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 282012Z - 290212Z
 
SUMMARY...ANOMALOUSLY HIGH MOISTURE VALUES COUPLED WITH DAYTIME
HEATING COULD LEAD TO LOCALLY HEAVY RAINFALL/ENHANCED MONSOON
CONDITIONS ACROSS NV.  FLASH FLOODING IS POSSIBLE.

DISCUSSION...PRECIPITABLE WATER VALUES OF AROUND 1.25" -- THREE
STANDARD DEVIATIONS ABOVE NORMAL -- TO THE NORTH OF AN UPPER LEVEL
LOW ARE LEADING TO EARLY THUNDERSTORM DEVELOPMENT ACROSS PORTIONS
OF SOUTHEAST CA, NV, AND ADJACENT NORTHWEST AZ.  WITH THE MOISTURE
AVAILABLE, RAINFALL RATES OF 1.5" AN HOUR ARE POSSIBLE.  THE SPC
MESOANALYSIS PAGE SHOWS MIXED LAYER CAPES OF 1000-1500 J/KG ACROSS
PORTIONS OF SOUTHEAST CA, SOUTHERN NV, AND WESTERN UT.

SEVERAL PIECES OF MESOSCALE QPF GUIDANCE ADVERTISE LOCAL AMOUNTS
OF 2-3", WHICH COULD CAUSE FLASH FLOODING/DEBRIS FLOWS ACROSS THE
REGION.  AFTER SUNSET, CONVECTION SHOULD BEGIN TO WANE AS THE
REMAINING AVAILABLE CAPE SLOWLY EXHAUSTS.  FLASH FLOODING IS
POSSIBLE IN THIS ENHANCED MONSOON REGIME.

ROTH

ATTN...WFO...FGZ...SLC...PSR...VEF...LKN...SGX...REV...HNX...
STO...

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

LAT...LON   40321187 37321222 33931350 33221580 34091685 36001803
            37711949 38711864 40171556 40751371 40321187