Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
914
FXUS66 KSEW 310243
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
743 PM PDT Sat May 30 2026
.SYNOPSIS...
An upper level ridge will slowly build across the
Pacific Northwest this weekend, resulting in a gradual warming
trend into early next week. Temperatures will peak on Tuesday,
resulting in Minor to Moderate HeatRisk. Onshore flow will
increase Wednesday with upper troughing approaching Western
Washington late in the week.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
No evening updates for the short/long term discussions. -HPR
A mix of clouds and sunshine this afternoon with continued weak
onshore flow across Western Washington. Temperatures remain
relatively cool today, with highs in the upper 50s to mid 60s.
Upper level ridging will gradual build into Western Washington
beginning Sunday and continuing into early next week. This will
result in a warming trend across the area. Highs on Sunday will
peak in the 60s to low 70s, with Monday afternoon temperatures
reaching the 70s, with low 80s south of Olympia and near
interior Grays Harbor County. An upper level low located over
Montana on Monday will also spread high clouds into Western
Washington, particularly during the afternoon.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
The upper ridge will
remain situated over Western Washington on Tuesday before the
ridge begins to flatten midweek. A brief thermal trough will
build into the region on Tuesday, which results in Tuesday being
the warmest day of the week with light offshore flow.
Widespread highs in the upper 70s to mid 80s are expected. The
potential for low 90s Tuesday afternoon will also exist from
Olympia southwards and into interior Grays Harbor and Mason
Counties. Widespread Minor to Moderate HeatRisk will exist on
Tuesday. Despite the warm air temperatures, rivers and lakes
remain cold. If you`re heading out on the water, always wear a
life jacket and take precautions for the cold water. In addition
to the warm temperatures, daytime RH values will dip between 20
to 30% with light east flow - see fire weather section for more
details.
Ensembles are generally consistent in the upper ridge slowly
flattening by Wednesday, resulting in increasing onshore flow.
Temperatures will cool by midweek, with forecast high
temperatures on Wednesday in the 60s and 70s. Onshore flow will
continue on Thursday. Ensembles begin to show a deeper trough
developing across British Columbia by late next week into the
following weekend. There is a notable uptick in POPs by late
Friday into Saturday with the upper troughing, in addition to
cooler temperatures next weekend. JD
&&
.AVIATION...
Upper level troughing over the northeastern Pacific will maintain
southwesterly flow aloft tonight before becoming more westerly by
early Sunday morning. Northwesterly flow aloft is expected to be in
place by Sunday afternoon as an upper level ridge starts to build
offshore. Onshore flow continues in the low levels with surface
winds speeds generally ranging 5-10 kts for the TAF period.
VFR conditions in place over W WA this early evening and while there
may be some increase in mid-level cloudiness in some spots tonight
and early Sunday morning, cloud bases expected to remain well within
VFR thresholds with minimal impact to terminals expected. Any
increase in cloud cover will diminish into the day Sunday as upper
level ridging becomes a greater influence over the area.
KSEA...VFR conditions with scattered clouds between 6000-7000 ft for
the TAF period.Some additional cloudiness possible at the terminal
Sunday morning before clearing again by afternoon. Northerly winds 5-
10 kt for the period, although speeds in the overnight and early
morning hours are more likely to inhabit the lower end of that
range. North to northwesterly winds increase to 8-12 kt Sunday
afternoon.
14/18
&&
.MARINE...
Small craft advisory strength westerlies will persist across
the central and eastern Strait of Juan de Fuca tonight into
early Sunday morning before easing. The increased onshore flow
will also bring gusty northwesterly winds to 25 kt to Admiralty
Inlet at times tonight. Winds will then ease across the majority
of the area waters on Sunday as high pressure builds across the
coastal waters, though portions of the coastal waters will see
an increase of northwesterly winds which could approach small
craft criteria at times Sunday afternoon and evening. This
pattern will also allow for waves to rise and steepen to 7-9 ft
at a period of around 7-9 seconds. Winds will gradually ease
and waves will subside towards 5-7 ft heading into Monday as
high pressure weakens over the region. A thermal trough then
looks to develop along the coast Monday night into Tuesday,
which will bring a brief period of offshore flow to the area
waters- but will not be strong enough to have any significant
marine impacts.
A frontal system will then move across the area waters
Wednesday into Thursday, resulting in the return of onshore
flow. Additional headlines will be likely for the central and
eastern Strait of Juan de Fuca as onshore flow increases
Wednesday night. Seas will primarily range between 6-8 ft.
14
&&
.FIRE WEATHER...
An upper ridge will result in a drier pattern
Monday and Tuesday with maximum temperatures reaching the 80s
(and a few spots in the low 90s) by Tuesday. Light offshore flow
is expected late Monday into Tuesday as a brief thermal trough
develops. At this time, winds are not expected to be strong,
however, a few locations within the Cascades could see gusts in
excess of 20 MPH. In addition, minimum RH values will lower
into the 20 to 35 percent range for most locations away from the
water. However, this stretch of warm, dry conditions will be
short-lived as onshore flow resumes by Wednesday bringing higher
RHs for the second half of the week.
&&
.HYDROLOGY...
The daily hydrology discussion has ended until the
start of the next rainy season; it will only be updated during
this time as needed.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 7 AM PDT Sunday for Central U.S.
Waters Strait Of Juan De Fuca-East Entrance U.S. Waters
Strait Of Juan De Fuca.
Small Craft Advisory until 5 AM PDT Sunday for Admiralty Inlet.
&&
$$
NWS SEW Office Area Forecast Discussion