Marine Weather and Tide Forecast for Toledo, OR

SHORT TERM
Now through Friday Night...Rainfall is currently ongoing across the region this afternoon in addition to breezy winds as a warm-frontal boundary pushes overhead and moisture associated with a prolonged Atmospheric River continues to stream overhead. Model integrated waver vapor transport values near 500kg/m*s persist for another 48+hrs is associated with a moderate strength atmospheric river, but it will be the wobbles of this moisture longitudinally through Friday evening which constitutes an area of uncertainty and will help to modulate the axis of the heaviest rainfall. In this regard, the two time periods to watch locally will be tonight into Thursday morning and Friday into Friday evening during which rainfall rates locally will be maximized. There is high confidence that somewhere within the Pacific Northwest will see significant rain, even potentially even in the valley but where exactly is still under review - likely somewhere between Salem and Kelso with the highest amounts in the Oregon Coast range. The long period of rain will produce some hydrological concerns which will be discussed in the "Hydrology" section below.

Rainfall projections remain highly sensitive to the atmospheric river placement and supporting dynamics like the frontal boundary placement/progression tonight and again Friday into Friday evening. In Portland and across the north Willamette Valley, NBM 72-hour totals ending early Saturday morning (close to a storm-total) range roughly 2 inches on the low end (10th percentile) to around 5.5 inches at the high end (90th percentile). Along the north Oregon Coast Range, probabilities span from roughly 4 inches at the low end to over 9 inches at the high end within that same time frame. These values, especially on the high-end, in combination with periods of higher rainfall rates have the potential to drive small stream and urban flooding beyond river-flooding concerns and promoted the issuance of a Flood Watch.

As far as snowfall is concerned main threat is over the south Washington Cascades where a Winter Storm Warning remains in effect for the Gifford Pinchot Natl Forest and Mt Adams through Thursday night to account for a brief surge in precipitation on that day. Additional totals through this period range from 5-12 inches at 2500-3000 ft up to nearly 25 inches above 4500-5000 ft. The location of the atmospheric river will ultimately be key. The area of concern sits right on the southern edge of the cold airmass, and 850 mb temperatures are right around -4 deg C.
If the cold air dips further south, then the snow ratios will increase and accumulation will rise. Several high-resolulation models like the NAMNEST also present a interesting "dynamic cooling" scenario across the lower elevations of southwest Washington Friday morning when the cooler air on the north side of the frontal boundary and high precipitation rates combine to artificially push snow levels lower, potentially near 500ft.
There is significant uncertainty as whether this will actually unfold and confidence is very low due to the complexity of the set-up, but's it's something we'll have to watch closely.
-99/27

LONG TERM
Saturday through Tuesday night...Rainfall tapers late Saturday as weak ridging develops. This ridge of high pressure will come into play on Sunday and Monday though as yet another atmospheric river is on deck. A broad low pressure system forms in the Gulf of Alaska on Saturday night. Ensemble 500 mb heights show good consistency between clusters in the ridge amplifying, a deep digging trough over the northern Plains and the low pressure system in the Gulf of Alaska staying to the north. About half of the clusters show a drier solution, while the other half favor rain. Vapor transport again shows a spike in values on Monday into Tuesday but uncertainty is quite high. If the ridge remains dominate we will see high temperatures well above climatology. For example in Eugene on Monday, the high temperature spread is around 67-73 degrees F (25th to 75th percentiles) with a 10% chance of seeing temperatures as high as 75 degrees. Further north in Kelso, WA the max temperature spread is closer to 55-65 degrees F with a 10% chance of highs of 67 degrees F.

There is high uncertainty overall in the long-term forecast so we will be continuing to evaluate as time passes. -27

AVIATION
MVFR conditions (primarily CIGs ) continue at inland terminals while LIFR/IFR conditions persist at coastal terminals.
Expect these conditions to last through the TAF period, with the exception of the possibility of MVFR conditions at KAST after 06Z Thu, and VFR conditions at KEUG between 00Z and 06Z Thu. Steady rain will continue throughout the airspace through the TAF period. Low end MVFR conditions will be possible if heavier rain bands pass over terminals. Winds will also be a concern through this TAF period, with southerly to southwesterly wind gusts increasing through all north- south aligned terrain, especially for for coastal and Willamette Valley terminals. Expect wind gusts up to 35-40 kt at coastal terminals until around 06Z Thu (highest gust magnitudes at KONP). As for the Willamette Valley, expect wind gusts up to 30 to 35 kt from now until before 12Z Thu. LLWS is a threat for many inland sites, especially for airports that are not susceptible to southerly surface winds like KTTD.

KPDX AND APPROACHES...Steady rain continues through the TAF period, with MVFR CIGs and occasional MVFR VIS expected to persist through the TAF period. Expect southerly to southwesterly wind gusts up to 30 kt from now until around 06Z Thu. Southerly to southwesterly winds up to 50 kt at 3000 ft through around 06Z Thu.
With surface wind gusts above 20 kt, the LLWS threat is not as significant. However, east approaches will likely be affected due to strong winds aloft, with speeds in the 50-60 kt range between 3000-5000 ft. ~12

MARINE
A strong frontal boundary moves over the waters, bringing varying conditions over the next 24 to 48 hours.
Southwest winds will continue to increase through this afternoon, bringing Gales Force winds (34+ kt) over all of the waters through this evening. The strongest gusts will be located within 10 NM of the coast due to nearshore enhancement, allowing Gale Force winds to persist a bit longer compared to the waters beyond 10 NM. Gale Warnings are in effect until 10 PM PDT this evening for the outer waters (beyond 10 NM) and until 2 AM PDT Thursday for the inner waters (within 10 NM), including the Columbia River Bar. During this time, seas will also become steep and hazardous, continuing beyond the Gale Warning time. With seas expected to build to around 13 to 15 ft at 10 to 11 seconds, a Hazardous Seas Warning has been issued for the outer waters from 10 PM this evening to 5 AM PDT Thursday. Small Craft Advisories will follow as seas remain elevated, with a Small Craft Advisory in effect for the inner waters by 2 AM Thursday and outer waters by 5 AM Thursday. The Small Craft Advisories will continue until late Thursday.

As the front finally exits southward on Friday, winds and seas will finally ease to below hazard criteria. As high pressure builds over the Northeast Pacific, winds will shift northerly Friday into the weekend while seas continue to ease below 5-6 ft through this weekend.
~12



HYDROLOGY
Hydrologic concerns increase today through Friday as a atmospheric river brings a prolonged period of moderate to heavy rainfall to portions of western Oregon and southwest Washington. While confidence is high that a moisture plume will impact the region, confidence remains moderate regarding where the heaviest rainfall will set up in conjunction with the two primary impulses of rainfall - tonight into Thursday morning and again on Friday. While most main-stem rivers have less than a 5% chance of minor flooding, a few of our "flashier" rivers have greater chances. The Pudding River at Aurora, Johnson Creek near Sycamore, and the Wilson/Trask near Tillamook are expected to reach minor Flood Stage with a 5-20% to reach moderate.
River responses will likely vary in time due to rainfall duration and location, with some likely occurring late tonight through Saturday, and others occurring late Thursday through Saturday. The most likely outcome at this time is elevated river levels and within-bank rises, though trends will need to be monitored.

PQR WATCHES/WARNINGS/ADVISORIES

OR...Winter Weather Advisory until 5 PM PDT this afternoon for ORZ126- 127.

WA...Winter Storm Warning until 5 AM PDT Friday for WAZ211.

PZ...Small Craft Advisory until 2 PM PDT this afternoon for PZZ210.

Small Craft Advisory from 2 AM to 5 PM PDT Thursday for PZZ210- 251>253.

Gale Warning until 2 AM PDT Thursday for PZZ210.

Gale Warning until 2 AM PDT Thursday for PZZ251>253.

Gale Warning until 10 PM PDT this evening for PZZ271>273.

Hazardous Seas Warning from 10 PM this evening to 5 AM PDT Thursday for PZZ271>273.

Small Craft Advisory from 5 AM to 5 PM PDT Thursday for PZZ271>273.