Marine Weather and Tide Forecast for Ocean Park, WA

DISCUSSION
Tuesday afternoon through Monday...Visible satellite imagery early Tuesday afternoon shows stratus remains socked into the interior valleys except for some clearing occurring in the Portland Metro due to light east winds from the Gorge. In most lowland areas outside of the Portland Metro, stratus will remain into tomorrow and likely into Thursday as a strong inversion under high pressure will keep winds and mixing very limited. Due to this limited mixing, an Air Stagnation Advisory has been issued for the central and southern Willamette Valley through Thursday morning. Stagnant air will allow for poor air quality. For locations under stratus, limited diurnal temperature fluctuations are expected with high temperatures in the upper 30s to low 40s and low temperatures in the mid to lower 30s. Outside of the stratus, daytime temperatures will peak in the mid 40s to low 50s.

Ensemble guidance continues indicating an upper wave and associated very weak decaying surface front moving through the area from the north on Thursday, pushing the high pressure farther west over the Pacific. Moisture associated with this front is limited with only 15-30% chance of limited precipitation over the far northern Oregon and SW Washington higher terrain. Limited accumulation is expected. This wave should be enough to finally mix out the stratus layer, though that may be temporary as ensemble clusters suggest strong high pressure over the eastern Pacific will begin moving closer to the coast Friday into the weekend, allowing for a surface inversion and fog/stratus formation once again.

NBM is confident that colder air will also be funneled into the PacNW behind this front, though just how cold will be determined by the exact setup of the ridge. For the interior lowlands, NBM has a 20-60% chance of low temperatures falling below 30 degrees on Friday morning but much higher chances at 70-90% Saturday through Monday mornings. For probabilities of 25 degrees, cities have a 10-40% chance Saturday through Monday mornings, highest probabilities on Sunday, but outlying areas have higher probabilities up to 70%. Temperatures along the coast are expected to be in the low 30s, and higher elevations are expected to fall into the teens to low 20s. -HEC

AVIATION
Not much change as strong high pressure remains over the region, resulting in a persistent pattern with a low stratus deck and areas of fog continuing for all inland terminals through at least Wednesday morning. The exception is at KTTD where low clouds are currently scattering out as breezy east winds develop. Winds will remain light and variable elsewhere. Similar to yesterday, expect the ongoing stratus deck to remain in place through the day with widespread LIFR to IFR cigs, except at the immediate coast where skies where skies should remain mostly clear.

PDX AND APPROACHES...Expect LIFR to low-end IFR cigs to remain in place through Wednesday morning with light and variable winds around 5 kt or less. /DH

MARINE
High pressure remains in place over the waters through the weekend, resulting in persistent northerly flow with winds generally staying under 20 kt. A northwesterly swell will also remain in place with wave heights generally ranging between 6 to 10 ft with a dominant wave period between 13 and 17 seconds. With seas near 10 ft this afternoon through Wednesday morning, have issued a Small Craft Advisory for all marine zones during that time. Have also issued a Small Craft Advisory for the Columbia River Bar for the same time period. Seas along the Columbia River Bar will peak near 12 ft late this afternoon into the early evening hours, as this is when a very strong ebb current of 6.41 kt will occur.

A weak frontal passage Thursday through Thursday night will likely bring breezier northerly wind with gusts between 20-25 kt, mainly for the outer coastal waters. Otherwise, conditions will remain relatively quiet. -TK/DH

PQR WATCHES/WARNINGS/ADVISORIES
OR...Air Stagnation Advisory until 10 AM PST Thursday for ORZ114>118.

WA...None.

PZ...Small Craft Advisory until 10 AM PST Wednesday for PZZ210- 251>253-271>273.