Area Forecast Discussion
Issued by NWS Portland, OR

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789 FXUS66 KPQR 080531 AAA AFDPQR Area Forecast Discussion...UPDATE National Weather Service Portland OR 930 PM PST Sat Feb 7 2026 Updated Aviation discussion .SYNOPSIS...A frontal system will continue to bring widespread rainfall to the Pacific Northwest this weekend, although snow levels remain above the Cascade passes through Sunday. Cooler and showery weather then continues Sunday night into early next week, with light snow accumulations at pass-level. A drier pattern returns midweek before rain chances increase late in the week. && .SHORT TERM...
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Now through Sunday Night...A wet pattern is setting up for the remainder of the weekend and into early next week as upper level ridging shifts east and a large trough moves over the PacNW. Southwesterly flow has set up in the mid and upper level, helping bring plenty of moisture to the region while a frontal system approaches from the west. Satellite and radar imagery depict plenty of cloud cover and areas of light rain over NW OR and SW WA. Southwesterly flow will maintain snow levels between 6000-8000 feet through early tonight so snow will be limited to the Cascade peaks during this time. Still expecting an area of low pressure to develop offshore along the boundary as the front moves inland, a feature which tends to slow or stall the progression of the front inland. A stalled boundary would locally increase the duration of heavier rain rates and observed rainfall, however given very dry antecedent conditions through January across the region, even higher-end rainfall totals present only a limited risk for urban and other poor-drainiage flooding, and more widespread areal or river flooding remains very unlikely. Slowing the boundary will also delay snow levels from dropping over the Cascades. Snow levels across the SW WA Cascades should drop to between 4500-5000 feet as the boundary stalls oriented NE-SW which will leave the NW OR Cascades snow levels between 5500-7000 feet. Behind the stalled front, a shortwave in the mid levels will move eastward, dislodging the front and supporting continued rain over the region through much of Sunday. Probability of one inch of rainfall through Sunday night remain greater than 80% for much of the area with the exception portions of the northern Willamette Valley, Portland/Vancouver metro, and the I-5 corridor in WA which could see a bit of rainshadowing from the Coast Range. Better moisture is expected in the Willamette Valley allong the I-5 corridor so generally expect higher totals south compared to north of Salem. Terrain enhancement will also increase totals over the Coast Range and Cascades which have a 10-40% chance of reaching three inches or more. -19 .LONG TERM...Monday through Friday...The cold front is expected to move through the area late Sunday evening with shower activity continuing in the post-frontal environment. Snow levels will also drop below pass level, generally 3000-4000 feet by Monday morning. Light, sub-advisory criteria accumulations are expected with a low (10-20%) of exceeding 6 inches in 24 hours through Monday evening. Models did come up slightly on these probabilities so something to keep in mind and watch for changes as the system progresses. Shower activity diminishes Monday night as drier air moves in and heights increase. Ensembles show good agreement in a dry period Tuesday through Thursday as shortwave ridging moves in overhead. Seasonable temperatures are expected through much of the work week. Models show signs that the dry pattern breaks down again late next week and into the weekend but exact timing and precipitation details are unclear at this times. -19
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&& .AVIATION...
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Strong southwest flow aloft as an upper jet is streaming moisture across the area through Sunday. A front will remain stalled over western Oregon producing more moderate rainfall across southern parts of the forecast area, which could result in reduced vsbys of 2SM or less. Otherwise, expect widespread MVFR conditions tonight into Sunday morning. IFR to LIFR conditions likely to continue at the coast through 10z Sunday (60-70% chance), before probabilities decrease to around 30%. A period of IFR conditions inland becomes more likely (30-50%) around 10z Sunday, before conditions are expected to improve later Sunday afternoon as the front pushes farther south and east. KPDX AND APPROACHES...MVFR conditions as a band of light rain streams over the area. CIGs around FL015 expected to persist through 10z. Then, probabilities for IFR CIGs increase to around 40-50% between 10z-16z Sunday. Flight conditions expected to gradually improve through Sunday afternoon, with around a 70% chance of VFR conditions after 22z Sunday as showers develop behind the front. Light south to southeast winds expected. /DH
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&& .MARINE...A system moving through the waters tonight will keep an active conditions across all waters. As the system continues to move inland, expect southerly gusts up to 30 kt with intermittent gusts up to 40 kt possible (60-90%) through around 8PM tonight. Seas will also remain elevated around 9 to 14 ft at 12 to 14 seconds. As the system moves further inland, look for southerly winds to become westerly, before becoming easterly late tonight. A quick moving disturbance on Sunday will bring a short period of north/northwesterly winds, before returning to a more traditional westerly pattern by Monday. Seas during this time frame will also remain elevated as a fresh westerly swell returns to all waters. This will keep seas above 10 ft through at least the middle of next week. Therefore, have extended the current suite of Small Craft Advisories through at least Sunday evening. Weak high pressure returns by the middle of the week and will provide a lull in the active weather with conditions falling below Small Craft Advisory thresholds. However, this looks to be short lived as a broad, upper level low looks to dive southward out of the Gulf of Alaska. This system currently, looks to bring elevated winds as well as seas building into the low to mid teens. /42 && .PQR WATCHES/WARNINGS/ADVISORIES...
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OR...None. WA...None. PZ...Small Craft Advisory until 4 AM PST Monday for PZZ210-251>253- 271>273.
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