MESOSCALE PRECIPITATION DISCUSSION 0762
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
733 PM EDT FRI NOV 04 2016
 
AREAS AFFECTED...OLYMPIC PENINSULA OF WA 
 
CONCERNING...HEAVY RAINFALL 
 
VALID 042330Z - 050830Z
 
SUMMARY...STRONG MOIST ONSHORE FLOW WILL LEAD TO A FEW HOURS MDT
TO HVY RAINFALL IN OLYMPIC PENINSULA WITH SOME FLOODING CONCERNS
POSSIBLE. 

DISCUSSION...GOES-W SATELLITE LOOPS DENOTE A LARGE/DEEP UPPER LOW
CENTERED NEAR 48N141W WITH FOCUSED SSE TO SELY WARM CONVEYOR BELT
IN ADVANCE FOCUSED TOWARD THE OLYMPIC PENINSULA OVER THE NEXT
12-18HRS. SATELLITE AMV TO 140-150 KTS WILL BE SLIPPING NORTHWEST
OF THE AREA OF CONCERN ALONG WITH SUBTLE SHORTWAVE LIFTING NORTH
ON THE WARM CONVEYOR HAS ALREADY PROVIDED DECENT RGT ENTRANCE/DPVA
ASCENT FOR EARLY/HIGHER ELEVATED STRATIFORM RAIN SHOWERS TO
APPROACH THE COAST AT THIS TIME MOISTENING THE LOWER ATMOSPHERE IN
ADVANCE OF AXIS OF DEEPER MOISTURE.  BLENDED TPW IMAGERY INDICATES
THIS AXIS REMAINS FAIRLY NARROW...THOUGH CURRENT PASS SHOWS SOME
HIGHLY SUSPECT VALUES OVER 1.5" THINKING EARLIER PASS WITH VALUES
OF 1-1.25" SEEMS REALISTIC.

CONCURRENT BLENDED RAIN RATE IMAGERY VALUES ARE UP TO .25"/HR
INDICATE THIS RIVER'S POTENCY ALREADY AT THIS TIME...WHILE
850-700MB SSWLY FLOW OF 50/70KTS RESPECTFULLY PROVIDES FLUX INTO
OROGRAPHICS SUGGESTIVE OF RATES UP TO .25"/HR ARE LIKELY AND NEAR
.5"/HR AS THE MAIN AXIS COMES THROUGH AROUND 08-09Z AND  SHOULD
POSE SOME FLOODING CONCERNS IN PRONE RIVERS THAT ARE FED OUT OF
THE HIGHER TERRAIN SUCH AS THE SKOKOMISH.  EXPECTATION IS FOR
RATES OVER .1"/HR IN THE OLYMPICS TO BE TIMED ABOUT 02-03Z. 
TOTALS OF 1.5-2.5" ARE EXPECTED IN THE HIGHEST PEAKS OF THE
OLYMPICS WITH NEAR 1" ALONG THE SW COAST OF WA POSSIBLE.
 
GALLINA

ATTN...WFO...PQR...SEW...

ATTN...RFC...NWRFC...

LAT...LON   48402467 48162392 48132311 47982273 47392310 
            46942342 46722403 47312426 47902461 48302473