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fxus66 kpqr 241006 

Area forecast discussion
National Weather Service Portland or
305 am PDT sun Sep 24 2017

Synopsis...expect mostly sunny skies Sunday, other than some morning
coastal stratus. The next front arrives Mon, with increasing chance
of light rain. High pressure builds later Tue, and remains over the
region through end of next week. This will allow for dry weather,
with above normal temperatures under some offshore flow.


Short through upper level ridge will
move onshore over the pac northwest later tonight and Sunday, which will
bring a warm and dry end to the weekend. National oceanic and atmospheric administration satellite imagery
showing plenty of mid and high clouds well offshore. But also shows
the low stratus now forming along the coast. These low clouds and
patchy fog, will eventually burn off later this morning. Then will
just have partly to mostly sunny skies with mild temperatures. Not
much fog inland, though will keep mention of patchy fog this am.

The mid/high clouds offshore will gradually increase over the region
tonight into Mon am as a weak front approaches. Weak front well to
the northwest today will push into the region later Mon and Mon
evening. But, not a lot of moisture with the front. Models in fair
agreement, so will not vary trends much away. Will keep increasing
chance of rain along the coast on Mon, and into the interior late in
the day into the evening. But again, with spotty precipitation with
the front, rainfall amounts will be light and sporadic. Still think
best threat of rain will be to the north, and much less threat as
move south towards Lane County.

Upper ridge will build over the region on Tue, with decreasing
clouds. Will see somewhat warmer temperatures, thanks to increasing
light offshore flow.Rockey.

Long term...upper ridge slowly pushes inland Wed and Thu, moving
east towards the northern rockies Fri. Low level flow remains
offshore Wed through Fri as the inverted surface trough drifts
offshore and weakens. This will bring warmer than normal temps to
the region including the coast, with the warmest days likely to be
Wed and Thu. By Fri night models in general agreement with pushing a
weak shortwave through the Pacific NW, pushing down upper heights
and allowing a weak cold front to move in. While still likely too
dry to carry any sort of mentionable pop, the flattened flow should
still allow some clouds back in, while cooling temps down a few

Aviation...VFR conditions inland with patchy IFR conditions
along the coast. Expect stratus to fill in more along the coast
within the next few hours. Still an isolated chance of cigs
developing at one or two sites inland, but expect mostly VFR

Kpdx and approaches...mostly VFR conditions through the period.
Small chance (less than 20 percent) that MVFR cigs develop at the
terminal this morning. /Bentley


Marine...quiet marine weather continues through Sunday and into
next week with light winds less than 15 knots and seas less than
6 feet. North winds will start to increase late in the day on
Tuesday as the thermal tough builds up the coast. Small craft
strength winds are likely and will begin in the southern waters
before expanding northward. These gusty winds will likely be
short lived as the gradient relaxes and winds switch to offshore
by late in the day Wednesday. /Bentley


Pqr watches/warnings/advisories...



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