Marine Weather and Tide Forecast for Idaville, OR

SHORT TERM
Now through Sunday night...Mid and upper level clouds continue to move over the area with the thickest cloudcover over southwest Washington. Mostly clear skies over the southern Willamette Valley will allow temperatures to cool more than most of the area. A frost advisory remains in effect until 8 am for the southern Willamette Valley and the Upper Hood River Valley, mainly above 1500 feet. Temperatures are expected to drop into the mid 30s, allowing for areas of frost to develop. The rest of the inland lowlands are expected to drop into the upper 30s to low 40s.

An upper level trough over the Aleutian islands will progress eastward toward the PacNW through the day, helping amplify shortwave ridging over the region. This will continue supporting the warming trend today with inland highs reaching the low to mid 70s while coastal areas will see highs in the upper 50s to mid 60s. A weakening cold front approaches late Saturday but is expected to lose steam as the upper low begins to shift more southeast instead of east. Light shower activity is possible over the waters but only and increase in upper level cloud cover is expected over most of the area during the evening and overnight hours. Overnight lows moderate into the mid to upper 40s tonight as cloud cover increases and daytime temperatures trend upward, eliminating the threat for frost/freeze potential for the next few days.

Highs on Sunday are expected to be similar to Saturday with highs a degree or two warmer but ultimately still in the low to mid 70s inland and upper 50s to mid 60s along the coast. There is a chance for urban locations around the Portland/Vancouver metro to reach 80 despite increasing cloud cover. Probabilities are 30-60% as far west as Banks, south to Aurora, and west to Latourell. -19

LONG TERM
Monday through Friday...The aforementioned trough will slow its eastward progression on Sunday, eventually pinching off from the main upper level flow into a closed low off the PacNW coast on Sunday. This feature becomes more influential heading into the next work week. Cluster analysis shows increased agreement for Monday with the center of the closed low remaining off northern California. That said, increasing cloud cover is still expected as heights aloft decrease over the area. Mild temperatures are still expected with highs in the upper 60s to low 70s inland and upper 50s to low 60s along the coast.

Come Tuesday, there remains some uncertainty among the ensembles. Trends point toward the upper low beginning to shift onshore which would bring cooler temperatures and increasing PoPs over the region. However, there is still a ~70-30 split among the ensembles favoring this progression which means there is still chance for mild and dry conditions. Locations farther south and west will see the transition to cooler, wetter conditions earlier given the location of the upper low.
There is much better agreement for Tuesday night into Wednesday being cool and wet. Cluster analysis shows good agreement in the closed low moving east and becoming an open wave. Ridging begin building back into the region Thursday and Friday, supporting a warming trend along with drier conditions. -19

AVIATION
VFR conditions expected to prevail through the TAF period. High level clouds continue to move over the area with a few breaks in the southern half of the Willamette Valley. COuld see some patchy frost develop on elevated or metal surfaces where temps drop into the mid 30s, mainly around KEUG. Expect skies to trend clearer through the day. Variable winds around 5 kt or less for most terminals, except slight tightening of KTTD-KDLS pressure gradients will result in easterly winds around 5-10 kt in the far east Portland Metro (KTTD). Along the coast, light offshore winds tonight turn more southwesterly after 18z Sat. This offshore flow along the coast will help prevent low marine stratus from developing.

KPDX AND APPROACHES...VFR conditions through the TAF period with high SCT/BKN clouds gradually decreasing on Saturday. Variable winds around 5 kt or less. Light easterly winds develops through the Columbia River Gorge after 12z Sat, but not expected to reach KPDX. -19/10

MARINE
Benign conditions continue through the weekend.
Southerly winds to around 10 kt expected today with seas remaining less than 5 ft.

There is higher forecast uncertainty for winds and seas early next week as an area of low pressure offshore approaches the coast. The placement of the low will determine the conditions across the waters, with the forecast at this lead time favoring increasing onshore flow through Wednesday, when WNW gusts may reach 20-25 kt beyond 30 NM. Higher winds and a freshly arriving NW swell may push seas to 10-12 ft Wednesday into Thursday.

Very strong ebb currents will continue across the Columbia River Bar each morning through Tuesday. With seas expected to build slightly by early next week, a steep ebb chop may necessitate Small Craft Advisories in the hours around peak flow each day. -19/36

PQR WATCHES/WARNINGS/ADVISORIES

OR...Frost Advisory until 8 AM PDT this morning for ORZ116>118-121.

WA...None.

PZ...None.