MESOSCALE PRECIPITATION DISCUSSION 0402
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1007 PM EDT THU JUN 30 2016
 
AREAS AFFECTED...SOUTHEAST NV...SOUTHWEST UT...NORTHWEST AZ...FAR
EASTERN CA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 010207Z - 010600Z
 
SUMMARY...VERY HEAVY CONVECTIVE RAINS WILL PROMOTE SOME ADDITIONAL
FLASH FLOODING OVER THE NEXT COUPLE OF HOURS...WITH CONDITIONS
EXPECTED TO IMPROVE BY LATE EVENING.

DISCUSSION...VERY COLD CONVECTIVE TOPS ASSOCIATED WITH SLOW-MOVING
THUNDERSTORMS CONTINUE OVER PORTIONS OF ESPECIALLY FAR SOUTHEAST
NV AND INTO NORTHWEST AZ WHERE HEAVY CONVECTIVE RAINS HAVE BECOME
QUITE WELL-ORGANIZED OVER THE LAST FEW HOURS. THE CONVECTION IS
BEING ENHANCED BY A STRONGLY UNSTABLE BOUNDARY LAYER...ESPECIALLY
ACROSS FAR EASTERN CA AND INTO SOUTHEAST NV...AND ALSO WITH
PRESENCE OF RATHER DIFFLUENT FLOW ALOFT TO THE EAST OF A WEAK MID
LEVEL TROUGH OVER SOUTH-CENTRAL CA.

ADDITIONAL FLASH FLOODING IS EXPECTED OVER AT LEAST THE NEXT
COUPLE OF HOURS OVER ESPECIALLY PARTS OF FAR EASTERN CA AND INTO
FAR SOUTHEAST NV AND NORTHWEST AZ WHERE HEAVY CONVECTIVE RAINS AND
FLASH FLOODING ARE ONGOING. THE LATEST HRRR GUIDANCE SUPPORTS
ADDITIONAL RAINFALL AMOUNTS OF AS MUCH 2 TO 3 INCHES...WITH
ISOLATED HEAVIER AMOUNTS. THIS WILL BE SUPPORTED BY INTENSE
RAINFALL RATES OF UP TO 1.5 INCHES/HR WHICH IS BEING FACILITATED
BY PWATS OF UP TO NEAR 1.75 INCHES.

CONDITIONS ARE EXPECTED TO IMPROVE BY LATE-EVENING AS INCREASING
LOW LEVEL CINH/BOUNDARY LAYER STABILIZATION ENSUES. WILL CONTINUE
TO MONITOR.

ORRISON

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

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

LAT...LON   37941239 37031123 35631215 34371363 33971456 
            34151532 34981567 36541503 37711385