Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS66 KSEW 310422
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
920 PM PDT SUN AUG 30 2015

.SYNOPSIS...AN UPPER LEVEL TROUGH WITH EMBEDDED DISTURBANCES WILL
KEEP THE WEATHER COOLER AND WETTER THAN NORMAL THROUGH WEDNESDAY.
THURSDAY AND FRIDAY WILL BE A BIT DRIER BUT STILL UNSTABLE AS AN
UPPER LOW MOVES SE THROUGH THE AREA. THE LOW WILL MOVE INLAND OVER
THE WEEKEND FOR WARMER AND DRIER CONDITIONS.

&&

.SHORT TERM...AS A BROAD UPPER TROUGH REMAINS OVER THE
REGION...EXPECT THE WEATHER TO REMAIN COOL AND UNSETTLED. TONIGHT
MAY BRING A BRIEF HIATUS FROM SHOWERS IN SOME AREAS...HOWEVER AS
ADDITIONAL SHORTWAVE DISTURBANCES MOVE THROUGH THE UPPER
TROUGH...EXPECT RAIN AT TIMES THROUGH WEDNESDAY. THE SURFACE
GRADIENT WILL REMAIN SOUTHERLY THROUGH WEDNESDAY AS WELL...KEEPING
LOW LEVEL WINDS FROM THE SOUTH. HOWEVER...THE GRADIENT WILL NOT BE
NEARLY AS STRONG AS THIS PAST SATURDAY AND ANY SURFACE WINDS WILL BE
LIMITED TO 20 MPH FOR THE MOST PART. JSMITH

.LONG TERM...ON THURSDAY AND FRIDAY AN UPPER LOW EMBEDDED IN THE
UPPER TROUGH WILL SWOOP SOUTHEAST THROUGH THE AREA...BRINGING A FEW
MORE PERIODS OF SHOWER ACTIVITY...AND THE MOUNTAINS AND PUGET SOUND
CONVERGENCE ZONE WILL HAVE THE GREATEST THREAT OF SHOWERS. SURFACE
GRADIENTS WILL BE WEAK DURING THIS TIME AND SURFACE WINDS WILL BE
LIGHT. OVER THE WEEKEND THE UPPER LOW WILL MOVE EAST OUT OF THE AREA
FOR DRY WEATHER AND SOME MORE SUNSHINE. JSMITH

&&

.AVIATION...A WEAK FRONT WILL APPROACH THE AREA FROM THE NORTHWEST
TONIGHT MOVING THROUGH THE NORTHERN PORTION OF THE AREA ON MONDAY.
LIGHT RAIN HAS ALREADY BEGUN ALONG THE NORTH COAST AND NORTHWEST
INTERIOR AS OF 04Z. LIGHT RAIN WILL SLOWLY SPREAD SOUTH THROUGH THE
AREA OVERNIGHT INTO MONDAY MORNING WITH THE RAIN FINALLY REACHING
KOLM 15Z-18Z. AHEAD OF THE RAIN CEILINGS 6000-8000 FEET. CEILINGS
LOWERING TO 3000-4000 FEET WITH THE LIGHT RAIN...2000-3000 FEET
ALONG THE COAST AND NORTH INTERIOR. LIGHT RAIN WILL CONTINUE INTO
THE AFTERNOON HOURS.

KSEA...CEILINGS ABOVE 5000 FEET LOWERING DOWN TO 3000-4000 FEET WITH
THE ONSET OF LIGHT RAIN 12Z-15Z. CEILINGS REMAINING NEAR 3000 FEET
INTO THE AFTERNOON HOURS. SOUTHERLY WINDS 8 TO 12 KNOTS. FELTON

&&

.MARINE...SOUTHERLY PRESSURE GRADIENTS INCREASING TONIGHT AS ANOTHER
FRONTAL SYSTEM APPROACHES FROM THE NORTHWEST. EXPECT SMALL CRAFT
ADVISORY SOUTHERLY WINDS OVER ALL WATERS BUT THE CENTRAL STRAIT BY
LATE TONIGHT. SMALL CRAFT ADVISORY WINDS WILL CONTINUE OVER THE
INTERIOR WATERS MONDAY MORNING BEFORE EASING MONDAY AFTERNOON. A
SERIES OF WEAK SYSTEMS WILL MOVE THROUGH THE AREA TUESDAY AND
WEDNESDAY. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...NONE.

PZ...SMALL CRAFT ADVISORIES COAST...ENTRANCES TO THE STRAIT...
     ADMIRALTY INLET AND THE INLAND WATERS.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.