MESOSCALE PRECIPITATION DISCUSSION 0334
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
825 PM EDT WED JUL 08 2015
 
AREAS AFFECTED...NORTHERN CA...NORTHWEST NV...EXTREME SOUTHERN OR 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 090024Z - 090300Z
 
SUMMARY...SLOW MOVING CELLS HAVE THE POTENTIAL TO PRODUCE HEAVY
RAIN/LOCALIZED FLASH FLOODING THROUGH 03Z.

DISCUSSION...CELLS CAPABLE OF PRODUCING HEAVY RAINFALL WERE
EMBEDDED WITHIN A BROKEN AREA OF SHOWERS AND THUNDERSTORMS LATE
THIS AFTERNOON.  THESE CELLS WILL CONTINUE TO BE CAPABLE OF
PRODUCING HEAVY RAINFALL FOR A FEW MORE HOURS.  AT THAT
POINT...THERE SHOULD BE A DECREASE IN COVERAGE AND RAINFALL
INTENSITY.

WHILE CELLS FORMED EARLIER TODAY IN AN ENVIRONMENT WITH STRONG
INSOLATION AND LITTLE IN THE WAY OF CIRRUS...THE MOST ACTIVE
CONVECTION HAS BEEN FIGHTING AN INCREASING CANOPY OF ANVIL CIRRUS
OVER THE PAST FEW HOURS. IN RESPONSE...THE NUMBER OF CELLS THAT
HAVE BEEN PRODUCING HEAVY RAINFALL HAVE BEEN SHOWING A GRADUAL
DECREASE ON RADAR AND SATELLITE IMAGERY. 

EVEN SO...THERE SHOULD BE SOME CELLS CAPABLE OF PRODUCING HEAVY
RAIN THROUGH ABOUT 03Z OR SO GIVEN THE SUPPORT OF SPEED DIVERGENCE
IN THE MID LEVELS AND DIFLUENCE AT JET LEVEL.  

THE MESOSCALE MODELS HAVE BEEN STRUGGLING TO CAPTURE MORE DETAILS
OF WHERE THE HEAVIEST RAINFALL WILL OCCUR IN THE SHORT TERM...SO
WE ARE LARGELY NOWCASTING THE SHORT TERM TRENDS IN TERMS OF
POSITION.  MAXIMUM RAINFALL RATES ON THE ORDER OF ONE INCH PER
HOUR ARE EXPECTED.

BANN

ATTN...WFO...EKA...MFR...MTR...REV...STO...

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

LAT...LON   42242165 41942017 40992008 40381944 39281841 
            38871959 40132107 39802177 39222177 38962211 
            38762252 39282312 40322354 41662301