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Area forecast discussion 
National Weather Service Portland or 
238 am PDT sun Jul 06 2008 


Synopsis...a weak Pacific front has moved well east of the Cascades 
early this morning. Higher pressure will begin building in over 
southwest Washington and northwest Oregon today...then strengthen 
Monday through Wednesday for warmer and dry weather. A weak system 
passing by to the north will likely increase the onshore flow late in 
the week. 
&& 


Short term...plenty of clouds across the forecast area and near the 
coast this morning in the onshore flow behind the weak front that 
moved through Saturday and Saturday evening. National Weather Service 
Doppler radar shows the last bunch of showers along the west slopes 
of the northern Cascade zones early this morning and they appear to 
be decreasing...and may mostly end not much after sunrise. Decent 
onshore flow today will likely make it take some time for the clouds 
to clear today...but an upper ridge does build this afternoon with 60 
meter height rises at 500 mb...in combination with the surface 
starting to bulge northward. Temperatures will likely be up a couple degrees 
today but not much above normal in the inland areas. 


Expect more clearing overnight tonight as the high pressure continues 
to build...except for some clouds persisting along the north coast 
that will edge back down the Columbia River toward Portland early 
Monday. As high pressure continue to build Monday expect what low 
clouds there are to clear rather early for lots of sunshine and 
warming temperatures. 850 mb temperatures support interior temperatures reaching 
into the lower or possibly middle 80s Monday afternoon. 


A pretty decent upper ridge will squash any marine layer and confine 
it to the immediate coast during the middle week period. 850 temperatures 
support temperatures inland reaching 90 or even into the lower 90s Tuesday 
and Wednesday. Tolleson 


Long term...models show decent upper ridging continuing through middle 
week with temperatures above 90 likely in the inland areas. Later in the 
week the medium range models show onshore flow developing that should 
increase the marine layer at the coast and spread it inland in the 
late night and morning hours...bringing cooling to the interior. Some 
timing differences in the GFS vs European model (ecmwf) with the GFS faster with a 
short wave moving through Thursday and ridging again by the weekend. 
The European model (ecmwf) is a bit slower...especially with any subsequent ridging. 
GFS ensembles show some members supporting the European model (ecmwf) so have trended 
that direction. Could see some drizzle at the coast but will not add 
that yet until details become clearer. Tolleson 
&& 


Aviation...a few light showers will continue to move into the 
Cascades this morning in the wake of a weak frontal passage last 
night. VFR and areas of MVFR ceilings will continue this morning 
before lifting and clearing later this afternoon as the flow begins 
to turn more offshore in response to a building ridge. 


Kpdx and approaches...areas of MVFR ceilings will continue this 
morning before skies begin to clear later this morning as high 
pressure builds overhead. 
&& 


Marine...10 to 12 feet west swell moving through buoy 46005...so 
expect this swell to reach the coast by this afternoon. Seas should 
just barely touch 10 feet in the coastal waters this afternoon through 
tonight. Other marine concern will be strengthening north winds as high 
pressure builds offshore today. These winds will likely continue for 
much of the week. 
&& 


Pqr watches/warnings/advisories... 
or/WA...Small Craft Advisory for hazardous seas Cape Shoalwater to 
Florence this afternoon through tonight. 
Small Craft Advisory for winds Cascade Head to Florence 
this afternoon through tonight 
Small Craft Advisory for rough Columbia River bar this 
morning and again this evening. 


&& 


Preliminary point probability of precipitation (probability of measurable precipitation) 
AST -0000 pdx 10000 sle 10000 eug 10000 
$$ 


More weather information online at... 
http://weather.Gov/Portland 


This discussion is for northwest Oregon and southwest Washington from 
the Cascade crest to 60 nautical miles offshore. The area is commonly 
referred to as the forecast area.