Marine Weather and Tide Forecast for Ridgefield, WA

SHORT TERM
Now through Monday Night...Radar and surface weather observations from early Saturday afternoon depicted a large swath of light to moderate stratiform rain falling across all of southwest WA and northwest OR from the coast to the Cascades. This area of rain is in response to a moisture-rich shortwave trough rotating southward around the backside of a closed upper level low centered over eastern WA/OR and western ID. With stratiform rain/limited instability in place through the remainder of the day, decided to manually lower NBM thunder probabilities to less than 15% to ensure thunderstorms are not mentioned in the forecast. Admittedly, there is a shallow layer of conditional instability below 750-800 mb, which is helping drive embedded convective cells in the Cascades/foothills, however these cells are not nearly deep enough to suggest lightning and/or hail will occur. Instead, locations that do get hit directly from embedded convective cells will see briefly enhanced rainfall rates. Note most locations have received anywhere from 0.25-0.75 inches of rain over the past 24 hours, however locations in the western Willamette Valley near the eastern slopes of the coastal mountains have generally received less than 0.40" while locations in the Cascades/foothills have received closer to 0.75-1.0 inches or more. With rain continuing to fall, these totals will only increase.

Persistent rain will eventually end from north to south Saturday evening/night as the aforementioned shortwave trough shifts into southwest OR. That said, scattered rain showers will linger over the area through Sunday morning, mainly in the mountains. Expect showers to come to an end for all locations by Sunday afternoon, aside from the Cascades where there is a 15-30% chance of showers through most of the day. Temps will be noticeably warmer with highs in the low to mid 70s rather than mid to upper 50s. The exception will be at the coast where highs in the 60s are expected. Weak shortwave ridging on Monday will bring dry weather with even warmer temps for inland areas. The NBM suggests high temps will most likely top out around 80 degrees or slightly warmer (70-90% chance). Meanwhile, highs in the 60s are likely to continue for coastal locations. -TK

LONG TERM
Tuesday through Friday night...A 500 mb shortwave trough is still set to move eastward over western WA/OR on Tuesday, likely bringing increasing mid and high level clouds. Despite the increase in cloud cover, no precipitation is expected with this trough due to a layer of relatively dry air at lower levels. Temps on Tuesday look to be fairly similar to Monday with highs near 80 degrees inland and 60s at the coast.

Beyond Tuesday, models and their ensembles show less agreement regarding precipitation chances and amounts. While it does appear a broad upper level trough will move over the area late Wednesday into Thursday, it is unclear how amplified this trough will be and if there will be precipitation with it. Currently near 30% of the total ensemble space amongst the GEFS/GEPS/ENS suggests the trough will be slightly deeper compared to the remaining 70% of the ensemble space.
This is largely driven by the GEFS, which is also showing the highest QPF amounts of any of the three ensemble systems, albeit with considerable model spread as there are still a small handful of members showing no rain at all while the wettest members are over 0.5 inches. Meanwhile, all ensemble members from the ENS show measurable rain, but with less overall model spread as around 75% of members are showing amounts less than 0.1 inches. The most likely outcome at this time is for insignificant rain amounts ranging between a trace and 0.1 inches to the north a line extending from Yachats to Eugene to Oakridge. Regardless of whether it rains or not, the overall synoptic scale setup and continuation of onshore flow will favor seasonable temperatures for this time of year with no signs of impactful heat through Friday. -TK

AVIATION
An associated weak surface front continues to move through the region, bringing widespread stratiform rain and a mix of MVFR/IFR conditions (IFR chances: 10-20% inland and 30-50% coastal). Deteriorated IFR conditions will most likely be related to isolated and heavier showers. Coastal terminals could see temporary LIFR conditions, with guidance suggesting a 10-20% chance at KONP through most of the TAF period. Expect increased southerly to southwesterly winds (more westerly along the coast), with gusts up to 20 kt until 00-03Z Sunday. Additionally, there is a 10-20% chance of thunderstorms along the coast and in the southern Willamette Valley until 00-03Z Sunday. After 00-03Z Sunday, wind and rain will weaken and MVFR/IFR stratus will remain throughout the airspace until at least 17-18Z Sunday.

PDX AND APPROACHES.. MVFR conditions will likely persist through most of the TAF period, possibly beginning to clear out and improve to VFR by 19-20Z Sunday. Southerly winds around 8-12 kt with an occasional gusts up to 18-20 kts will decrease after 00-03Z Sunday. Rain will begin to taper off between 00-06Z Sunday. ~Hall

MARINE
Unsettled conditions continue over the waters as a weather system continues to push through the region. Northwesterly to westerly winds remain at 10-20 kt with gusts up to 20-30 kt until late tonight. As a result of this weather system, seas are around 7-10 ft with a 8-10 second period. A Small Craft Advisory remains in effect for the outer waters through 5 AM Sunday.
Additionally, another Small Craft Advisory remains in effect for the inner waters through 9 PM today for combined Small Craft winds and seas. Winds and seas decrease on Sunday as high pressure begins building over the eastern Pacific. Expect winds 5-10 kts and seas 4-6 ft by Sunday morning, continuing into Monday. These generally quieter conditions are expected to persist into the midweek. ~Hall/HEC

PQR WATCHES/WARNINGS/ADVISORIES

OR...None.
WA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for PZZ251>253.

Small Craft Advisory until 5 AM PDT Sunday for PZZ271>273.