Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
198
FXUS66 KSEW 192133
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
233 PM PDT Sun Apr 19 2026
.SYNOPSIS...
Mostly dry and warm weather will continue early this week. A low
will track inland Tuesday and Wednesday with the next chance of
precipitation for the region. Temperatures will also cool
descent amount with this pattern change. The end of the week is
favored to remain dry, with temperatures returning to mild.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
An upper level ridge sits in the Idaho/Montana Rockies this
afternoon, with an upper level low offshore. The ridge axis
tilts northwest towards southern B.C.. Strong southerly flow
ahead of the low will continue today into Monday. Temperatures
have had no problem warming in this pattern, with several
locations already hitting 70 and higher this afternoon. Winds
remain light out of the north today, but will turn towards the
south Monday afternoon ahead of the low moving ashore.
The flow will become split Monday into Tuesday as the low cuts
off from the jet in southern Canada. The low will continue to
dig southward towards California, with a trough expected to
swing through as early as Tuesday from the in Canada (aided by
some diffluence from the low to the south). Monday will continue
the dry and warm pattern for one more day (high temperatures
again reaching the low to mid 70s in the central/south sound).
Moisture reaches the region by Tuesday with a 50-70% chance of
rain (highest probabilities in the Cascades/Olympics and the
Pacific Coast). There is also a 20% chance of thunder for the
Cascades Tuesday afternoon (particularly along the crest).
Precipitation amounts are expected to remain light overall, but
the Cascades may see locally heavier precipitation with any
convection that develops. Snow levels will be greater than
6,000 ft, leaving snow likely to just the volcanoes/high peaks
in the mountains. Winds remain light for most on Tuesday, but
the Cascades could see a few gusts to 20-25 mph from the west
later in the day.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The southern low will track inland towards the Rockies on
Wednesday, with a trough from the Canada dipping southward
Wednesday/Thursday. This keeps precipitation chances lingering
Wednesday and into early Thursday. Wednesday will be the coolest
day of the week, with most highs remaining below 60. Ensembles
favor a dry and mild pattern returning late Thursday to finish
off the work week, with some disagreement into how strong/long
it will last into the weekend.
HPR
&&
.AVIATION...An upper level low will spin offshore tonight and
Monday off OR/CA, with ongoing dry weather across western WA.
The flow aloft is E to SE. VFR conditions prevail with a mix of
mid and high level clouds. 33
KSEA...VFR through the period. N winds around 10 kt, becoming
light NE this evening, then NW/N by 18Z Mon. 33
&&
.MARINE...Low pressure will spin offshore, off OR/CA, with light
offshore over western WA tonight and Monday. The low will shift
inland and weaken on Tuesday with onshore flow increasing.
Highest winds will be through the Strait of Juan de Fuca.
Onshore flow will continue through Thursday with high pressure
over the NE Pacific. Offshore flow may develop toward the end of
the week as a thermal trough forms along the coast. 33
&&
.HYDROLOGY...
No river flooding is expected over the next 7 days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion