Gale Watch 22, NWS Seattle, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
920 PM PDT SAT APR 2 2016

.SYNOPSIS...HIGH PRESSURE WILL MOVE ACROSS THE AREA TONIGHT AND
EARLY SUNDAY. A COLD FRONT WILL REACH THE AREA SUNDAY NIGHT. COOL
SHOWERY BLUSTERY WEATHER WILL BE OVER WESTERN WASHINGTON ON MONDAY.
THE SNOW LEVEL WILL FALL TO THE HIGHER CASCADE PASSES MONDAY. A
STRONG RIDGE WILL DEVELOP WEDNESDAY AND THURSDAY WITH TEMPERATURES
WARMING WELL INTO THE 70S THURSDAY AND FRIDAY.

&&

.SHORT TERM...CLOUDS LATE TONIGHT AND SUNDAY MORNING WILL BE MUCH
LESS WIDESPREAD AS SHORTWAVE RIDGING ALOFT SHIFTS THROUGH THE
REGION. A COLD FRONT WILL REACH THE AREA SUNDAY EVENING AND MOVE
INTO THE CASCADES BY MIDNIGHT SUNDAY NIGHT. THE TROUGH WILL GIVE
COOL...SHOWERY...AND BLUSTERY CONDITIONS TO THE AREA MONDAY. THE
SNOW LEVEL WILL FALL TO 3500 FEET MONDAY AFTERNOON AND EVENING. A
WARM FRONT WILL MOVE TROUGH THE AREA TUESDAY AND TUESDAY NIGHT.

.LONG TERM...STRONG RIDGING WILL DEVELOP ACROSS THE REGION ON
WEDNESDAY AND WILL REACH ITS MAXIMUM AMPLITUDE ON THURSDAY. BOTH THE
ECMWF AND GFS SHOW 500 MB HEIGHTS REACHING NEAR 580 DAM BY THURSDAY
AFTERNOON AND LOW LEVEL FLOW WILL BE OFFSHORE. IT IS APPEARING THAT
THURSDAY WILL BE THE WARMEST DAY OF THE YEAR SO FAR WITH HIGHS IN
CENTRAL AND SOUTHERN PORTIONS OF THE FORECAST AREA GETTING INTO THE
MID AND UPPER 70S. THE DGEX MODEL SHOWS LOWER 80S...WHICH WILL BE
POSSIBLE IF THE OFFSHORE FLOW DEVELOPS JUST A BIT MORE STRONGLY THAN
EXPECTED. HEIGHTS FALL STARTING FRIDAY AND A MARINE PUSH IS LIKELY
BY LATE IN THE DAY. BUT TEMPERATURES BEFORE THE PUSH BEGINS COULD BE
NEARLY AS WARM ON FRIDAY AS ON THURSDAY. EXPECT COOLING ON SATURDAY
WITH CONDITIONS REMAINING DRY AS MARINE AIR MOVES INLAND BUT UPPER
LEVEL RIDGING CONTINUES OVER WASHINGTON. ALBRECHT/19

&&

.AVIATION...UPPER LEVEL RIDGE EAST OF THE AREA WITH UPPER
LEVEL TROUGH DIGGING SOUTH OFFSHORE. LIGHT WESTERLY FLOW ALOFT
BECOMING SOUTHWESTERLY ON SUNDAY.

SURFACE GRADIENTS LIGHT TONIGHT AND WILL REMAIN LIGHT INTO SUNDAY.
THIS WILL KEEP THE STRATUS DEVELOPING OVERNIGHT WEST OF PUGET SOUND
SUNDAY MORNING.

COLD FRONT APPROACHING LATE SUNDAY WITH INCREASING MID/HIGH LEVEL
MOISTURE SUNDAY AFTERNOON. CEILINGS LOWERING TO THE 3500-5000 FOOT
LEVEL WITH THE ONSET OF THE RAIN SUNDAY EVENING.

KSEA...JUST SOME HIGH CLOUDS INTO SUNDAY AFTERNOON. CEILINGS
LOWERING
TO NEAR 4000 FEET 03Z-06Z MONDAY WITH THE ONSET OF THE RAIN.
NORTHERLY WINDS 4 TO 8 KNOTS WILL BECOMING LIGHT AND VARIABLE BY 12Z
SUNDAY. WINDS BECOMING SOUTHERLY SUNDAY AFTERNOON INCREASING TO 10
TO
15 KNOTS SUNDAY EVENING. FELTON

&&

.MARINE...SURFACE GRADIENTS LIGHT TONIGHT AS HIGH PRESSURE BUILDS
INLAND.
A COLD FRONT WILL SWEEP ACROSS THE AREA LATE SUNDAY NIGHT AND EARLY
MONDAY MORNING...FOLLOWED BY STRONG ONSHORE FLOW AND THE LIKELIHOOD
OF
WESTERLY GALES THROUGH THE STRAIT. THE ONSHORE FLOW WILL WEAKEN ON
TUESDAY...THEN HIGH PRESSURE WILL BE CENTERED DIRECTLY OVER THE
INLAND
WATERS ON WED. FELTON/HANER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 5 AM PDT SUNDAY CENTRAL AND
EASTERN STRAIT.

&&

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