339 
FXUS66 KPQR 131701 AAA
AFDPQR

Area Forecast Discussion...Update
National Weather Service Portland OR 
1001 AM PDT Sat Oct 13 2018

.SYNOPSIS...Classic dry autumn weather for a while, with mild days
and cool nights, perfect for pumpkin patching. Will also see breezy
easterly winds into early next week. 

&&

.UPDATE...Made a quick update to portions of the forecast today to
adjust for the low cloudiness presently in the Willamette Valley east
of Interstate 5. These clouds should clear out by noon or 1 PM. Also
tweaked temperatures downward a bit for tonight to bring some
stations more in line with current MOS guidance. While some sites
will remain breezy and in the 40s overnight, locations such as
Lebanon, Sweet Home, and Molalla can often be skipped over by east
wind situations like this, which in this case would allow them to
decouple resulting in min temps in the 30s. Wind-sheltered valleys of
the Cascades and Coast Range may also bottom out into the 30s if
winds go calm overnight. Otherwise, the thinking behind the previous
discussion remains valid.  Weagle

.SHORT TERM...Today through Monday...With jet stream well north of
the region, so goes the rain, staying in western Canada southward 
into central USA. With high pressure in control of our weather 
pattern well into next week we'll see dry weather with mild daytime 
temperatures, along with cool nights. 

Early this morning is the transition from onshore to offshore as high
pressure near the surface build over the interior of WA/OR. 
Satellite shows stratus along the coast begin to pull offshore or
dissipate.  The easterly gradients will increase through today, with
breezy east to northeast winds developing. This is not
uncommon to see such a pattern in October.  With the air somewhat
downsloping off the western Cascades and again down the west slopes
of the coastal mountains, will see warm afternoons this weekend.
While most areas inland will be in the 70s, would not be surprised to
see a few spots hit closer to 80 deg along the coast Sun. The winds
will also act to moderate overnight temps, with lows in the mid 40s
to mid 50s where winds continue. But, for areas where winds ease in
the night, the dry air mass will promote quick cooling, with
temperatures dropping into 30s with some frost possible, especially
on Sunday and Monday morning.	 Not much change in the pattern
through Mon, though pres gradients relax a bit by Mon, with winds
easing on Mon.	      /mh  Rockey. 


.LONG TERM...Monday night through Friday...Strong high pressure over
the region will move little through next week, maintaining dry
weather with mild days and cool nights.  Low level offshore flow not
as strong, which may lead to rather chilly nights over the interior
lowlands and mountain valleys. Very well may see our first freezes
for lowlands along the coast and mainly interior valleys next week.
This is not too far off from the average first freeze, which
typically is between Oct 15th and 25th. 		  Rockey. 

&& 

.AVIATION...A north-to-south line of IFR stratus extended from
eastern Clark County in SW Washington to the Umpqua Basin at 16Z.
Patchy IFR to LIFR fog was also noted along the central Oregon
coast, but was rapidly dissipating. Expect VFR across the area by
18Z as low-level flow becomes north to northeast. East surface
wind ramps up through the west end of the Columbia River Gorge
this afternoon, with gusts up to 45 kt likely. Breezy conditions
expected to develop elsewhere this afternoon and continue through
Sunday morning, especially along the coast and through east-to-
west oriented coastal drainages and saddles and passes through
the Cascades. 

KPDX AND APPROACHES...Patchy IFR stratus continues to linger
between KPDX and KTTD at 16Z, but will dissipate by 17Z. VFR
thereafter through Sunday morning. Increasing east surface wind
to develop at the terminal and vicinity this afternoon, with 
gusts 25 to 30 kt by late afternoon. Weishaar

&&

.MARINE...High pressure will prevail through at least the middle
of next week. Surface thermal low pressure along the south 
Oregon coast this morning expands north through tonight, 
maintaining small craft advisory strength winds over the outer 
waters through at least early tonight. Some local gusts to 25 kt 
still appear possible over the inner waters in the vicinity of 
the coastal gaps. Not enough support in the latest guidance, 
however, to warrant an advisory for the inner zones at this time,
but an advisory may be needed if these surface over a larger 
portion of the waters. Advisories may also be needed for some of 
the coastal waters on Sunday with the offshore pressure gradient 
remaining sufficiently strong. The offshore pattern weakens early
next week, with gusts returning to the 15-20 kt range by Monday.

Seas a little higher than expected this morning, with the
offshore buoys in the 6 to 8 ft range at 16Z. Buoy 089, just
outside the forecast area, hit 9 ft earlier this morning. Expect
wave heights today and tonight to remain constant, with the 
largest seas coincident with the strongest winds. Conditions will
be rather choppy through the weekend with a dominant period 
around 6 to 8 seconds due to the wind-wave contribution, as well 
as a pair of smaller swells. The largest seas will be over the 
outer waters, and may approach steepness criteria to warrant an 
advisory for hazardous seas. For now, forecast periods appear to
be long enough, around 9 seconds, to avoid square-sea conditions,
but this will need to be closely monitored. Weishaar

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory for winds until 11 PM PDT this evening for 
     Waters from Cape Shoalwater WA to Florence OR from 10 to 
     60 NM.

&&

$$

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This discussion is for Northwest Oregon and Southwest Washington
from the Cascade crest to 60 nautical miles offshore. This area is
commonly referred to as the CWA or forecast area.