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fxus66 ksew 230248 

Area forecast discussion
National Weather Service Seattle Washington
750 PM PDT sun Jul 22 2018

Synopsis...much above average temperatures will be the rule
through the week ahead across the inland portion of western
Washington. The coast will be cooler than the rest of the region
with low clouds or fog along the beaches at times.


Short term...mostly clear skies over West Washington according to current
satellite imagery and that trend looks to stay in place for the
duration of the short term over the interior. Low clouds and fog
have finally burned off for coastal locations...but looking for
those conditions to re-emerge later tonight and once again into
Monday morning.

An upper level ridge over the Pacific will result in the big
takeaway for the short term forecast...that being much above average
temperatures. Monday looks to be the warmest day as interior temps
will climb into the low 90s while Tuesday and Wednesday show only
slightly cooler by a degree or two...putting highs in the upper 80s
to right around 90. Heat impact level guidance for Monday is showing
that heat-related impacts will be likely...and as such may need to
update inherited forecast to issue a heat advisory for mostly the
south sound and SW interior zones...including Olympia and Tacoma.
Area of concern does stretch a little bit further north than may include the Seattle Metro as well. Will allow future
shifts to evaluate possible heat-related headlines for Tuesday or
Wednesday. Smr

Long term...from previous discussion...warm and dry weather
continues into next weekend. The ridge axis may bulge a bit toward
western Washington so there is a chance that the warmest days will
be around the end of the week or over next weekend. The coast will
continue to have cooling sea breezes, fog banks, or low clouds at
times--fog could squirt into the Strait of Juan de Fuca each night--
a pretty good westerly push is likely each evening in the Strait.
Looking the wrfgfs, there's little difference in the low cloud/0-
3kft cloud mixing ratio each day--and using that as a guide, there
is a chance that fog could even reach Whidbey Island starting
midweek, but for now I have only put a little fog on the coast each


Aviation...weak westerly flow aloft through Monday. Air mass stable
and mainly dry. Low level moisture and patchy IFR stratus along the
Washington coast. Otherwise mostly clear with VFR skies.

Ksea...clear skies through Monday. Surface winds north to northwest 5 to 10 kt
becoming NE after 04z or 05z before returning to north to northwest at 5 to 10
kt late Monday morning. Dtm/smr


Marine...surface high pressure over b.C. Will produce mostly light
or northerly flow over the waters through the week. Winds over the
coastal waters may approach small craft strength up to 20 kt at
times. Typical diurnally driven westerly winds will strengthen at
times in the central and eastern Strait possibly resulting in Small
Craft Advisory wind speeds. As such...a Small Craft Advisory remains
in effect for that area this evening. Dtm/smr


Sew watches/warnings/advisories...
Pz...Small Craft Advisory until midnight PDT tonight for central U.S.
Waters Strait of Juan de Fuca-East Entrance U.S. Waters
Strait of Juan de Fuca.

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