FXUS66 KPQR 261752

AFDPQR



Area Forecast Discussion

National Weather Service Portland OR

359 AM PDT Thu Jun 26 2025



.SYNOPSIS...Onshore flow will maintain cloudier weather and more

seasonable to slightly below normal temperatures through Friday.

Areas of light drizzle will remain possible later this morning

along the coast and for inland areas north of Salem. Warm and 

dry conditions return this weekend into early next week with 

inland high temperatures approaching or exceeding 90 degrees in 

many locations Sunday and Monday.



&&



.SHORT TERM...Now through Friday Night...Water vapor imagery 

shows little change in the upper level pattern this morning as 

longwave troughing spanning from the Gulf of Alaska into western

Canada keeps robust onshore flow focused over the Pacific 

Northwest. This pattern maintains extensive cloud cover west of 

the Cascades, with the vertical wind profiler at KAST showing a 

marine layer depth of around 3000 ft as of 3 AM Thursday. Not 

currently seeing any precipitation being reported around the 

region, but expect another round of light rain/drizzle to 

develop later this morning as the latest disturbance approaches

from offshore and provides some weak forcing, lingering into 

the afternoon across parts of southwest Washington. Once again 

do not expect more than a trace to a couple hundredths of an 

inch of precipitation through this evening, with areas along the

northern coast from Astoria to Long Beach showing a 10-15% 

chance to receive as much as a tenth of an inch of rain today. 

Any precipitation inland should largely be limited to areas 

from Portland northward as the central and south Willamette 

Valley remain dry. Much like Wednesday, expect that extensive 

cloud cover will again keep temperatures this afternoon a 

couple degrees below guidance as highs top out around 70 degrees

in the Willamette Valley and closer to the upper 60s across 

southwest Washington.



Onshore flow will maintain similar conditions on Friday, except

with any light rain or drizzle mostly staying confined to 

southwest Washington. Clouds will also have the potential to 

scatter out a bit more during the afternoon, allowing highs to 

end up closer to the low to mid 70s in the Willamette Valley 

while marine influences keep coastal communities down in the 60s

for another day. Onshore flow will also maintain breezy west 

winds through the central Columbia River Gorge each afternoon 

as winds gust to 25-30 mph in some spots around Hood River. /CB



.LONG TERM...Saturday through Wednesday... A stretch of warmer,

drier, and sunnier weather will commence on Saturday as models

continue to depict a building upper level ridge over the western

CONUS with a cutoff low developing over the California coast.

Increasing 500 mb heights will allow temperatures to jump back

up into the low 80s in the inland valleys on Saturday.

Temperatures still look to peak Sunday into Monday as the ridge

continues to amplify, with the NBM now depicting a 50-70% 

chance to reach 90 degrees in the Willamette Valley on Sunday 

and a 75-90% chance on Monday. Locations across interior

southwest Washington show notably lower probabilities to reach 

90 degrees, with highs in the 80s more likely from Kelso through

the Cowlitz Valley. Probs to reach 95 degrees have backed off 

somewhat for Monday, now sitting closer to 15-35% in most 

locations in the Willamette Valley. The mid 90s continue to 

represent a reasonable worst case scenario for heat on Monday 

as the chance to reach 100 degrees continues to reside in the 

low single digits. Temperatures look to level off somewhat 

beyond Monday, but will still remain well above normal as 

guidance keeps highs in the 80s for much of the rest of the 

week, showing around a 30-40% to reach as high as 90 degrees for

Tuesday and Wednesday.



The other forecast concernin the long term will be the 

potential for thunderstorms along the Cascades during the first 

half of next week, which will largely be dependent upon the 

evolution of the aforementioned cutoff low near the California 

coast. This will have the potential to draw monsoonal mid level 

moisture northward into our area in southeast flow aloft, which 

is often challenging for the NBM to resolve. A farther north 

position of the low will generally be more favorable for 

thunderstorms to reach into the central and northern Oregon 

Cascades. For now, will maintain a 15-20% chance of 

thunderstorms along parts of the Cascades both Monday and 

Tuesday afternoon, but will need to keep a close eye on how this

pattern evolves in the coming days. /CB



&&



.AVIATION...Onshore flow with marine stratus. Radar shows isolated

showers in the area but due to the dry lower atmosphere, rain is not 

reaching the ground. Biggest concern in regards to CIGs. The 

southern portions of the area (south of KSLE) are beginning to clear 

and will continue to do so over the next few hours. The northern 

portions will likely back build off of the Cascades.

Could see some partial clearing around KHIO but confidence is low in 

significant clearing. A weak front will pass over the area again on 

Friday maintaining similar conditions. 



PDX AND APPROACHES...MVFR CIGs through the early afternoon will 

slowly lift to VFR after 20Z Thu with a scattered deck in the 2000 

ft range. Winds will be northwesterly. Saturation will once again 

cause CIGs to lower once again to high end MVFR levels. 	-Muessle



&&



.MARINE...A series of weak fronts will pass over the waters

through the remainder of the week which will maintain generally 

westerly winds along with seas less than 6 ft. Each weak frontal

passage will result in a brief southerly wind shift. However, over

the weekend, as high pressure develops expect a northerly wind 

shift as is typical with our summer time patterns. Also, winds 

will begin to ramp up with a 75-90% probability of Small Craft 

Winds across all waters. Seas too will respond with general seas 

around 3-5 ft at 8-10 seconds with seas building towards 4-7 ft 

by this weekend and into the start of the upcoming week. 

/42-Muessle



&&



.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.

WA...None.

PZ...None.

&&



$$



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