Marine Weather and Tide Forecast for Eugene, OR

DISCUSSION
Visible satellite shows clear skies across northwest Oregon and southwest Washington this afternoon as morning stratus was much quicker to burn off than the past few days. This will help temperatures reach well into the 70s across most inland locations today, with marine influences keeping coastal areas closer to the upper 50s or low 60s. Little change is expected in the sensible weather over the next few days as deep upper level troughing over the NE Pacific maintains a broad onshore flow regime across the Pacific Northwest. This will equate to seasonable temperatures in the upper 70s in the inland valleys through Wednesday, with onshore flow keeping coastal communities cooler and cloudier. Tuesday has the potential to be the warmest day of the week, with the probability to surpass 80 degrees ranging from 60-80% from the Portland Vancouver Metro through the rest of the Willamette Valley on Tuesday afternoon.

Rain chances continue to look rather minimal and mostly confined to the coast through Wednesday as a pair of week fronts traverse the area. The first of these fronts approaches late Monday into Tuesday, but looks to fall apart offshore. Can't rule out a few sprinkles along the coast late Monday night into early Tuesday, but expect the rest of the area to remain dry.
The somewhat better chance for some light rain will come with the second weak front Tuesday night into early Wednesday, however, model QPF values remain on the meager side as coastal areas from about Tillamook County northward still only have a 30-40% chance to reach a tenth of an inch. Meanwhile, amounts have continued to dwindle further inland as the Portland area now only has about a 5% chance to even see a tenth of an inch through Wednesday morning. Will most likely see only a trace to a couple hundredths in the Portland Metro, with areas to the south from Salem to Eugene likely to stay dry.

After another dry and seasonable day on Thursday, chances for more substantial rainfall continue to increase Friday into Saturday as the deep upper level trough moves directly overhead.
Nearly all ensemble members now depict at least some measurable rain for locations in the Willamette Valley, with the chance to receive a wetting rain of a quarter inch increasing to around 40% in the Portland Metro and 20% from Salem to Eugene. Coastal areas and the higher terrain of the Cascades have the best chances for a wetting rain, with probabilities ranging from 50-60% in those areas. Regardless of exact amounts, confidence continues to increase in a wetter pattern with widespread showers likely across the area towards the end of the week, Can't rule out a few thunderstorms Friday into Saturday as cooling aloft yields steeper mid level lapse rates, but opted not include thunderstorms in the forecast at this time as the NBM currently only depicts around a 10% chance across the area.
Thunderstorm potential will likely ultimately depend on any breaks in the cloud cover which can help to generate surface based instability. It is worth noting that any thunderstorms would likely be accompanied by locally heavy rainfall given the abundant moisture which will be in place. /CB

AVIATION
Surface high pressure persists over the Northeast Pacific, keeping conditions VFR and northwesterly flow through most of the TAF period. The only exception will be the coast, where MVFR marine stratus will likely develop between 11-19Z Monday (30-40% chance of MVFR, with highest chances to the north).
Northwesterly winds around 5-10 kt for inland terminals will become light after 03-06Z Monday. As for the coast, expect northwesterly winds around 10-15 kt with gusts to 20-25 kt to continue until 03-05Z Monday, the becoming light thereafter.

*KTTD ASOS is currently INOP except for altimeter and will be AMD NOT SKED.

PDX AND APPROACHES...VFR conditions and clear skies are expected through the period. Northwesterly winds around 5-10 kt becoming light by 06-07Z Monday. ~Hall

MARINE
North/northwesterly flow continues, with diurnally driven peaks in the afternoon. Winds 15-20 kt with gusts to around 25 kt continue for south of Cape Falcon to Florence this through this evening. As a result, the Small Craft Advisory from Cape Falcon OR to Florence OR will remain in effect until 11 PM this evening.

A weak disturbance is expected to cross the region on Monday, supporting southerly winds late Monday and through Tuesday. A westerly swell is also expected to move into the waters late Monday, generally around 5 ft at 10 seconds. Combined seas still look to remain 7 ft or less through next week. -Batz

PQR WATCHES/WARNINGS/ADVISORIES
OR...None.
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for PZZ252- 253-272-273.