FXUS66 KSEW 220857

AFDSEW



Area Forecast Discussion

National Weather Service Seattle WA

157 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/...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 will continue to prevail across western 

Washington today. A weak and mostly dry front is moving across 

the area early this morning. This will bring increased ceilings 

this morning, but conditions are expected to remain mostly VFR. 

Chances for MVFR cigs this morning remain below 15-25% across 

the area terminals. Ceilings will lift and scatter through the 

late morning, with high clouds dominating the skies through the 

remainder of the day and tonight.



Winds this morning are mostly light and variable, through remain 

south/southeasterly through Puget Sound area. Winds are expected to 

continue to ease through the morning, switching to light northerly 

at around 19-20Z early this afternoon, increasing to around 8 to 12 

kt by 00Z Mon and remain like so through much of tonight.



KSEA...VFR conditions are expected to prevail through the TAF 

period. CIGs will gradually redevelop this morning as a dry front 

moves through the area. This will be relatively short lived as 

clouds scatter by this afternoon and high clouds prevail through the 

remainder of the period. S winds will gradually decrease through the 

morning, turning N by 20Z, and increasing to 8 to 12 kt after 00Z 

Mon through the end of the period.



62



&&



.MARINE...A weak and mostly dry front is currently traversing 

the coastal waters early this morning. Winds across the far 

northern portions of the coastal waters, as well as the west 

entrance to the Strait of Juan de Fuca remain a bit elevated 

with gusts up to 20-23 kt, but these winds should ease through 

the morning. Otherwise, high pressure will 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



&&



.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.



&&



$$