Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 091146
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
346 AM PST TUE FEB 9 2016

.SYNOPSIS...A STRONG UPPER LEVEL RIDGE AND LOW LEVEL OFFSHORE FLOW
WILL BRING ONE MORE SUNNY AND MILD DAY TO WESTERN WASHINGTON
TODAY. SOUTHWEST FLOW ALOFT WILL DEVELOP LATER TODAY AS THE RIDGE
MOVES EAST...ALLOWING EMBEDDED SYSTEMS TO BRING MORE CLOUDS AND
SOME RAIN AT TIMES FROM TUESDAY NIGHT THROUGH THE FIRST PART OF
NEXT WEEK.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE OVER
THE PACIFIC NORTHWEST EARLY THIS MORNING WITH THE RIDGE AXIS RIGHT
OVER WESTERN WASHINGTON. SOME PATCHY FOG HAS DEVELOPED ALONG THE
I-5 CORRIDOR FROM TACOMA SOUTHWARD AND ALONG THE HOOD CANAL AND
OVER THE NORTHWEST INTERIOR. FOR THE REMAINDER OF THE AREA SKIES
ARE CLEAR. WIDE RANGE OF TEMPERATURES AT 3 AM WITH EASTERLY WINDS
KEEPING THE COAST UP IN THE UPPER 40S WHILE IN THE WIND SHELTERED
AREAS TEMPERATURES ARE NEAR FREEZING.

UPPER LEVEL RIDGE SHIFTING EAST TODAY WITH THE RIDGE AXIS OVER THE
IDAHO PANHANDLE BY 00Z WEDNESDAY. FLOW ALOFT BECOMING
SOUTHWESTERLY BUT THE LOW LEVEL FLOW WILL REMAIN OFFSHORE.
TEMPERATURES ALOFT VERY WARM WITH THE SAND POINT PROFILER
INDICATING TEMPERATURES IN THE MID TO UPPER 60S AT 2500 FEET.
PARADISE ON MOUNT RAINIER AT ABOUT 5400 FEET IS REPORTING 58
DEGREES THIS HOUR. EVEN WITH THE RIDGE AXIS MOVING EAST AND THE
WEAKENING OFFSHORE FLOW WITH THE TEMPERATURES ALOFT SO WARM EXPECT
ANOTHER DAY OF HIGH TEMPERATURES WELL ABOVE NORMAL...IN THE MID
50S TO MID 60S WITH THE WARM SPOT ONCE AGAIN ALONG THE NORTH COAST
AND IN THE WESTERN FOOTHILLS OF THE OLYMPICS.

UPPER LEVEL RIDGE NOT MOVING MUCH TO THE EAST TONIGHT BUT
WEAKENING. LOW LEVEL FLOW REMAINING OFFSHORE. WEAK SYSTEM EMBEDDED
IN THE SOUTHWESTERLY FLOW ALOFT APPROACHING THE COAST BUT STILL
OFFSHORE BY 12Z WEDNESDAY. THE COMBINATION OF THE LOW LEVEL
OFFSHORE FLOW AND SOME INCREASING CLOUDS WILL KEEP LOW
TEMPERATURES MOSTLY IN THE 40S EARLY WEDNESDAY MORNING.

WEAK SYSTEM MOVING INTO THE AREA ON WEDNESDAY WITH THE BEST
CHANCES FOR RAIN ALONG THE COAST. WITH PLENTY OF CLOUD COVER HIGHS
WILL BE COOLER ON WEDNESDAY...MAINLY IN THE 50S.

TAIL END OF THE SYSTEM HANGING OVER THE AREA WEDNESDAY NIGHT
KEEPING CHANCE POPS IN THE FORECAST. NEXT SYSTEM EMBEDDED IN THE
SOUTHWESTERLY FLOW ALOFT STRONGER AND MORE ORGANIZED. MODEL
SOLUTIONS HAVE BEEN SOMEWHAT INCONSISTENT WITH THE SOLUTION TO
THIS FEATURE IN THE PREVIOUS RUNS. THE 00Z RUN SHOWS MUCH BETTER
CONSISTENCY WITH ALL THE MODELS BRING PRECIPITATION INTO THE AREA
ON THURSDAY. HAVE INCREASED THE POPS INTO THE LIKELY CATEGORY.
HIGHS ONCE AGAIN WILL BE IN THE 50S.

.LONG TERM...GOOD CONSISTENCY IN THE SHORT TERM SOLUTIONS
EXTENDING INTO THE LONG TERM ON THE 00Z RUN. SYSTEM ON THURSDAY
STALLS OVER THE AREA THURSDAY NIGHT WITH ANOTHER WAVE MOVING UP
THE BOUNDARY ON FRIDAY KEEP RAIN IN THE FORECAST FOR BOTH DAYS.
SYSTEM KICKING EAST FRIDAY NIGHT WITH AN UPPER LEVEL TROUGH MOVING
THROUGH ON SATURDAY FOR A CHANCE OF SHOWERS.LONG FETCH OF MOISTURE
MOVING ACROSS THE EASTERN PACIFIC SUNDAY INTO MONDAY. MODELS HAVE
BEEN WAFFLING A BIT ON WHERE THE JET WILL SET UP. PREVIOUS RUNS
HAVE HAD IT TO THE NORTH OF THE AREA. THE CURRENT SOLUTION POINTS
THE JET RIGHT AT WESTERN WASHINGTON WITH THE MOISTURE TAP ALL THE
WAY BACK TO NEAR 30N/155W. THE ECMWF IS MORE CONSOLIDATED WIT
WITH THE MOISTURE FETCH VERSUS THE GFS BUT BOTH MODELS ARE WET
FOR WESTERN WASHINGTON. HAVE INCREASED THE POPS INTO THE LIKELY
CATEGORY FOR BOTH DAYS. FELTON

&&

.AVIATION...LIGHT FLOW ALOFT WILL BECOME SOUTHERLY TODAY AS AN
UPPER RIDGE OVER THE AREA SHIFTS EAST. HIGH PRESSURE INLAND WITH
LOW PRESSURE OFFSHORE WILL CONTINUE TO GIVE OFFSHORE FLOW.
THE AIR MASS IS DRY AND STABLE. THERE WILL BE PATCHY SHALLOW FOG IN
A FEW SPOTS THROUGH DAYBREAK...OLYMPIA AND IN A FEW RIVER VALLEYS.

KSEA...FAIR SKIES AND A NE BREEZE BECOMING LIGHT AND VARIABLE LATER TDY.

&&

.MARINE...OFFSHORE FLOW TODAY. A WEAK WARM FRONT WILL BRUSH THE AREA WED.
ANOTHER FRONTAL SYSTEM WILL STALL JUST OFFSHORE THU AND FRI...MOVING INLAND
SAT. THE FRONTAL SYSTEMS WILL AFFECT MAINLY THE COAST WITH SMALL CRAFT
ADVISORY CONDITIONS THERE AND AT THE WEST ENTRANCE AT TIMES.

&&

.HYDROLOGY...RIVER FLOODING IS UNLIKELY THROUGH SATURDAY. THERE IS
SOME POTENTIAL FOR HEAVY RAINS OVER THE OLYMPICS BEGINNING SUNDAY
WHICH COULD CAUSE THE FLOOD PRONE SKOKOMISH TO REACH FLOOD STAGE
EARLY NEXT WEEK. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 3 PM PST THIS AFTERNOON FOR COASTAL
     WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 10 NM-WEST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 3 PM PST THIS AFTERNOON
     FOR GRAYS HARBOR BAR.

&&

$$

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