139 
fxus66 kmfr 301050 
afdmfr 


Area forecast discussion 
National Weather Service Medford or 
350 am PDT Sat Aug 30 2008 


Short term...an upper level trough is moving towards the region 
today...this will bring a cold pool over the area on Sunday. Then 
the trough will gradually shift east Sunday night. Cooler than 
normal temperatures are expected today through Monday. 


A cold front has moved inland and is currently moving east of the 
area early this morning. Low clouds have moved into Coos and 
Douglas counties and are extending into portions of Curry and 
Josephine counties. Some light showers have been reported...mainly 
along the coast and into the Umpqua. As the clouds continue to 
advance into the west side of Oregon...expect some additional light 
amounts through this morning...with a slight chance for light 
precipitation continuing along the Cascade foothills through 
today. Behind the front...cold air will be moving into the area as 
the upper trough moves over the area. This will bring cooler 
temperatures today through Monday...with coolest temperatures 
Sunday into Sunday night. Tonight temperatures are expected to 
lower into the middle 30s for locations in Klamath and lake counties. 
However...expect only patchy frost since north winds may keep more 
widespread frost from developing. 


Also...NAM and GFS indicate that as the cold pool aloft moves into 
place late tonight into Sunday and a shortwave rotates around the 
base of the trough...expect some additional low clouds to move into 
place with a slight chance for light showers tonight into 
Sunday...mainly over the coast and into the Umpqua and Cascade 
foothills. Snow levels will lower Sunday morning to around 5500 to 
6000 feet with the possibility of light snow over the Cascades. 


In addition...this trough will bring breezy and gusty conditions 
this afternoon through this evening...especially east of the 
Cascades. As the trough moves into the area tonight and 
Sunday...expect some continued breezy north winds especially for 
higher terrain and the east side. 


As the trough exists to east...expect clearing skies on Monday. 
This...combined with cold air in place will allow for colder 
temperatures Monday morning with lows reaching the lower 30s to 
middle 20s east of the Cascades and lows in the upper 30s to middle 40s for 
many west side valleys. 




&& 


Aviation...coast...areas MVFR ceilings with local IFR in fog expected 
through this morning...with conditions improving to VFR this 
afternoon. Then...MVFR ceilings will return to the coast becoming 
widespread Saturday evening. Inland...west of the Cascades in 
Oregon...MVFR ceilings mainly from the coast into Coos and Douglas 
counties and extending into the Illinois and rogue valleys will 
continue through this morning becoming isolated in the afternoon. 
Elsewhere VFR conditions. 




&& 


Previous discussion... /issued 854 PM PDT Friday Aug 29 2008/ 


The medium and long range outlook has been consistent over the 
past couple days. It will be a little warmer Monday but more 
noticeable warming Tuesday with temperatures near normal under 
weak eastern Pacific ridging through Friday. 




&& 


Mfr watches/warnings/advisories... 
or...none. 


California...red flag warning from 2 PM this afternoon to 11 PM PDT this 
evening for caz285. 


Pacific coastal waters...Gale Warning until 11 PM PDT this evening 
for pzz356-pzz376. 
Hazardous seas warning until 11 PM PDT this evening for pzz356- 
pzz376. 
Small Craft Advisory for winds until 11 PM PDT this evening for 
pzz350. 
Small Craft Advisory for hazardous seas until 11 PM PDT this 
evening for pzz350. 
Small Craft Advisory for winds until 5 am PDT Sunday for pzz370. 
Small Craft Advisory for hazardous seas until 5 am PDT Sunday 
for pzz370. 


$$ 


Cirrocumulus