613
FXUS66 KSEW 221533
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
833 AM PDT SUN MAR 22 2026
SYNOPSIS
A WEAK SYSTEM WILL BRUSH THE REGION THIS MORNING.
ACTIVE WEATHER RETURNS BY TUESDAY FOR MORE RAIN, HIGH ELEVATION
SNOW AND GUSTY WINDS. SHOWERS AND A CONVERGENCE ZONE WILL FORM
ON WEDNESDAY WITH ONSHORE FLOW. DRIER WEATHER WILL PREVAIL LATE
IN THE WEEK AND WEEKEND.
SHORT TERM /TODAY THROUGH TUESDAY/
NO MAJOR FORECAST UPDATES HAVE BEEN MADE THIS MORNING. A
DECREASING NUMBER OF RIVERS REMAIN IN FLOOD STAGE, BUT WILL
CONTINUE RECEDING. THE REST OF THE PREVIOUS DISCUSSION CAN BE
FOUND BELOW, WITH UPDATES TO THE AVIATION AND MARINE SECTIONS.
A WEAK FRONT WILL BRUSH THROUGH WESTERN WA THIS MORNING WITH
ISOLATED TO SCATTERED SHOWERS. HIGH PRESSURE WILL BUILD INLAND
THIS AFTERNOON FOR DRIER CONDITIONS. EXPECT PARTLY SUNNY
CONDITIONS WITH HIGHS IN THE UPPER 40S TO LOWER 50S.
HIGH PRESSURE AND OFFSHORE FLOW WILL PREVAIL ON MONDAY FOR DRY
WEATHER. MORNING LOWS WILL BE A LITTLE COOLER WITH LOWS IN THE
30S, AND TEMPS NEAR FREEZING AROUND THE SOUTH SOUND.
A STRONGER AND WETTER PACIFIC FRONTAL SYSTEM WILL IMPACT THE
AREA ON TUESDAY. THIS SYSTEM IS TIED TO A DEEP LOW SPINNING
OFFSHORE THAT WILL SHIFT NORTH OF HAIDA GWAII. THE MAIN THREAT
WILL BE GUSTY SOUTH WINDS, PRIMARILY COAST AND NORTH PART, WHERE
PROBABILITIES OF GUSTS EXCEEDING 45 MPH ARE THE HIGHEST. UP IN
THE MOUNTAINS, SNOW LEVELS ARE LOWEST OVER THE NORTHERN
CASCADES WHERE A FEW INCHES OF SNOW WILL FALL. SNOW LEVELS WILL
BE RISING OVER 5,000 FT IN THE CENTRAL CASCADES THUS MINIMIZING
IMPACTS TO I-90 AND US 2. RIVERS WILL SEE SMALL RISES BUT
ADDITIONAL FLOODING IS NOT ANTICIPATED. 33
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/
WE REMAIN UNDER MODERATE ONSHORE FLOW ON WEDNESDAY WITH HIGH
PRESSURE OFFSHORE AND DEEP LOW PRESSURE TO OUR NORTH. SNOW
LEVELS ARE LOWER, AROUND 2,500 FT, WITH SNOW IN THE CASCADES AND
PASSES. SHOWERS WITH A CONVERGENCE ZONE MAY ENHANCE SNOW
AMOUNTS NEAR STEVENS PASS. HIGH PRESSURE SHIFTS INLAND THURSDAY,
FRIDAY, SATURDAY FOR DRIER WEATHER ACROSS THE BOARD. EXPECT
WARNER HIGHS IN THE INTERIOR FRIDAY AND SATURDAY WITH LOWER 60S
POSSIBLE. DRY OFFSHORE FLOW WILL KEEPS LOWS COOL AND IN THE 30S.
33
AVIATION
ZONAL FLOW ALOFT WILL PREVAIL ACROSS WESTERN WASHINGTON TODAY.
A WEAK, DISSIPATING FRONT IS CURRENTLY MOVING INLAND ACROSS THE
AREA THIS MORNING. WHILE LATEST RADAR SHOWS A FEW SPOTTY SHOWERS
IN THE VICINITY OF KHQM AND KCLM, EXPECT MOST AREAS TO REMAIN
DRY AS THIS FRONT CONTINUES TO PUSH INLAND. THE MAIN IMPACT
FROM THIS SYSTEM HAS BEEN THE LOWERING OF CEILINGS TO MVFR FOR
MOST TERMINALS. CEILINGS WILL LIFT AND SCATTER THROUGH THE LATE
MORNING, WITH IMPROVEMENT BACK TOWARDS VFR CONDITIONS EXPECTED
AROUND 18Z. HIGH CLOUDS WILL DOMINATE THE SKIES THROUGH THE
REMAINDER OF THE DAY AND INTO TONIGHT.
WINDS THIS MORNING ARE MOSTLY LIGHT AT 4-7 KT AND REMAIN
SOUTH/SOUTHEASTERLY THROUGH THE PUGET SOUND AREA. THE EXCEPTION
HAS BEEN KBLI, WHERE WINDS HAVE PERSISTENTLY BEEN 8-12 KT AND
GUSTING TO 20 KT AT TIMES THIS MORNING. WINDS WILL THEN TRANSITION
TO LIGHT NORTHERLY FOR MOST PUGET SOUND TERMINALS BETWEEN
19-21Z AND INCREASE TO AROUND 8-12 KT BY 00Z MON. WINDS WILL
THEN REMAIN SO THROUGH MUCH OF TONIGHT.
KSEA...MVFR CIGS AT THE TERMINAL THIS MORNING AS A DISSIPATING
FRONT MOVES INLAND. LOWER CEILINGS SHOULD LIFT AND SCATTER
AROUND 18Z, WITH HIGH CLOUDS PREVAILING THROUGH THE REMAINDER
OF THE DAY. SOUTHERLY WINDS BETWEEN 4-7 KT WILL TURN NORTHERLY
BY 21Z AND WILL INCREASE TO 8-12 KT BY 00Z MON.
62/14
MARINE
A WEAK, DISSIPATING FRONT IS PUSHING INLAND ACROSS THE INTERIOR
WATERS THIS MORNING. WINDS ACROSS THE FAR NORTHERN PORTIONS OF
THE COASTAL WATERS AND ALONG THE WEST ENTRANCE OF THE STRAIT OF
JUAN DE FUCA HAVE EASED IN ITS WAKE. A FEW ISOLATED GUSTS TO
20-23 KT HAVE BEEN NOTED ACROSS THE NORTHERN INLAND WATERS THIS
MORNING AS THIS FRONT PUSHES THROUGH, BUT GENERALLY EXPECT WINDS
TO REMAIN BELOW SMALL CRAFT CRITERIA AS THIS SYSTEM MOVES THROUGH
THE AREA.
HIGH PRESSURE WILL THEN BUILD INTO THE AREA IN THE FRONT'S WAKE
AND CONTINUE TO DOMINATE ACROSS THE AREA THROUGH MONDAY. SEAS
WILL REMAIN IN THE 5-8 FT RANGE THROUGH MONDAY AS WELL. THE
FOCUS THEN TURNS TOWARDS TUESDAY AS A STRONG LOW PRESSURE SYSTEM
MOVES INTO THE REGION FROM THE SOUTHWEST. UNCERTAINTY REMAINS
TO THE EXACT TRACK OF THE SYSTEM, BUT STRONGER WINDS AND
INCREASING SEAS ARE LIKELY ACROSS THE COASTAL WATERS. THE NBM
INDICATES THAT AT LEAST SMALL CRAFT ADVISORY WINDS ARE VERY
LIKELY (>90%) ACROSS ALL THE COASTAL AND INTERIOR WATERS, WITH
40- 60% CHANCE OF GALE FORCE WINDS ACROSS THE COASTAL WATERS ON
TUESDAY. GEFS ENSEMBLE GUIDANCE CONTINUES TO SHOW A 50-70%
CHANCE OF SEAS EXCEEDING 20 FT TUESDAY NIGHT INTO EARLY
WEDNESDAY.
62/14
HYDROLOGY
RIVER CONTINUE TO RECEDE WITH DRY CONDITIONS. MOST
FLOOD WARNINGS WILL END TODAY. THE CEDAR RIVER AT RENTON WILL
REMAIN NEAR MINOR FLOOD STAGE THROUGH MONDAY DUE TO DAM
RELEASES. NO OTHER RIVER FLOODING EXPECTED OVER THE NEXT 7 DAYS.
SEW WATCHES/WARNINGS/ADVISORIES
WA...NONE.
PZ...NONE.
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