Marine Weather and Tide Forecast for Garibaldi, OR

SHORT TERM
Now through Monday Night...Clouds are beginning to dissipate in the northern portions of the forecast area while the southern potions remain under dense cloud cover. These clouds have been an inhibiting factor to significant daytime heating like we saw yesterday. However, where skies have cleared, seeing about a degree an hour of warming. To the south, a low aloft is spinning over Northern California. This low continues to be the main weather maker today as it encourages southeasterly flow and wrap around moisture. While radar has showed showers throughout the area, accumulation has been minimal. This is mainly due to the significant amount of dry air right at the surface and above 5000 ft. The precipitation has had the opportunity to evaporate before reaching the ground (this is called virga).

Overnight the low will shift east slowly which will enhance the precipitation potential more. Based on high resolution models, there is good consensus in precipitation falling along eastern Lane and Linn counties through Saturday morning. Accumulation expected to be highest along the lee side of the Cascades.
Because conditions will be showery, exact accumulation is difficult to narrow down. Under stronger showers where the atmosphere is moist enough, precipitation will be higher. In contrast, there are many areas that will see little to no accumulation. In addition to the precipitation, the east-west pressure gradient will reach around 10 mb. Expect gusty westerly winds through the Gorge, especially in the Upper Hood River Valley.

Onshore flow persists through the week which will keep temperatures moderated. -Muessle

LONG TERM
Tuesday through Friday...The weak ridge will break down on Tuesday as a eroding shortwave trough advects inland from the Northeast Pacific. This shortwave will produce more widespread showers over southwest Washington and northwest Oregon. This is a fairly fast moving system. Humidity between 850-250 mb will dry significantly which can be observed in soundings from the area. This will lead to lower humidity along the mountains and clear skies. On Wednesday, the ridge will intensify and a thermal trough will form along the coast. Winds aloft (above 850 mb) will transition to the northeast bringing in warmer air from east of the Cascades. In the afternoon the trough will shift east of the Cascades, then back to the west side in the evening.

The Willamette Valley temperature forecast has fairly good agreement in the long term. The warmest of the next week will be Thursday (when the ridge is at it's peak). The NBM shows a high temperature range in Eugene of 76-80 degrees F. Along the coast, that range is in the upper 60s. Will mention though that the potential downsloping effects off of the coast range could cause temperatures to be higher around Tillamook. In fact, in Hood River, the forecast is showing the 25th-75th percentile of temperatures at 80-82 degrees F which is incredibly narrow.
-Muessle

AVIATION
VFR flying conditions continue across much of the region as coverage of high clouds has increased from the east. A large upper-level low continues to spin over inland California, although rain showers will likely remain south of the region. The highest chances, 20-40%, for rain will be over the central Oregon Cascades, with less than a 15% chance of rain reaching EUG, and less than 10% elsewhere. Therefore, no impacts from light rain showers are expected at area terminals. Low-level cloud cover will otherwise increase across the region, with MVFR cigs favored at all terminals overnight. At inland sites, confidence in MVFR cigs is highest to the south, with a 60-80% chance for continued MVFR cigs at EUG through 18-20Z Sat. Both the duration and likelihood of MVFR cigs lessen to the north, with the shortest duration in the Portland area between 11-18Z Sat. Winds of 3-8 kt out of the south to southwest this evening will turn out of the northwest after 16-20Z Sat at all Willamette Valley terminals.

Along the coast, persistent MVFR cigs are likely for much of the period, and as inland, there is higher confidence to the south.
At ONP, MVFR cigs are very likely throughout the period, and there is 40-60% confidence in continued IFR cigs through 18-20Z Sat. To the north at AST, IFR cigs are expected overnight, most likely from 09-14Z Sat, with MVFR cigs otherwise favored through 20-22Z Sat. A brief improvement in flying conditions after 18-22Z Sat will give way to renewed MVFR/IFR conditions after 02-03Z Sun.
Northwest winds at 5-10 kt will continue through tonight, before increasing to 10-15 kt with gusts to 20 kt after 18-22Z Sat.

PDX AND APPROACHES...VFR conditions expected to continue into tonight beneath increasingly cloudy skies. There remains a 40-60% chance of MVFR cigs at 2-3 kft after 11-12Z Sat, continuing through mid-morning. VFR conditions will again be favored after 18Z Sat as low clouds dissipate. No vis restrictions are anticipated throughout the period. Winds around 5 kt out of the southwest overnight will turn out of the west to northwest, increasing to 5-10 kt after 16-18Z Sat. -Picard

MARINE
Winds gradually shifting northwest through this afternoon, with wind speeds increasing by tonight. Gusts may approach 25 kt by late this afternoon, particularly in the outer zones. This uptick in winds is coinciding with a building westerly swell, pushing combined seas toward 10 to 11 feet by Saturday. As a result, Small Craft Advisories will be in effect for all waters by this afternoon, with conditions likely persisting through at least Saturday. By late Saturday night and into Sunday, both winds and seasons will begin to ease as high pressure weakens slightly and moves inland. The start of next week looks to be rather quiet, with seas around 5 to 7 feet and wind gusts under 20 kt. -Hall/JLiu

PQR WATCHES/WARNINGS/ADVISORIES

OR...None.
WA...None.
PZ...Small Craft Advisory from 2 AM Saturday to 2 AM PDT Sunday for PZZ251>253.
Small Craft Advisory until 2 AM PDT Sunday for PZZ271>273.