Sunrise 5:57 AM   Sunset 8:21 PM Moonrise 2:35 AM   Moonset 12:44 PM

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PZZ255 Coastal Waters From Cascade Head To Florence Or Out 10 Nm- 847 Am Pdt Tue Sep 13 2022
.dense fog advisory in effect until 10 pm pdt this evening - .
Rest of today - SW wind to 5 kt. Wind waves sw 1 ft at 4 seconds. NW swell 2 ft at 9 seconds. Widespread dense fog and a chance of showers in the morning, then areas of dense fog in the afternoon. Tonight - N wind to 5 kt. Wind waves N 1 ft at 4 seconds. NW swell 3 ft at 9 seconds. Areas of dense fog in the evening. Patchy dense fog after midnight. Wed - N wind 5 kt. Wind waves N 1 ft at 4 seconds. NW swell 3 ft at 9 seconds. Patchy dense fog in the morning. Wed night - NW wind 5 kt. Wind waves W 1 ft at 4 seconds. NW swell 3 ft at 9 seconds. Thu - SE wind 5 kt, veering to W in the afternoon. Wind waves se 1 ft at 4 seconds, shifting to the W at 4 seconds in the afternoon. NW swell 3 ft at 10 seconds. Thu night - N wind 5 to 10 kt. Wind waves N 1 ft at 4 seconds. NW swell 3 ft at 10 seconds. Fri - N wind 5 to 10 kt. Wind waves 2 ft. NW swell 3 ft. Sat - NW wind 5 to 10 kt. Wind waves 2 ft. NW swell 4 ft.

PZZ200 218 Pm Pdt Thu May 2 2024
Synopsis for the southern washington and northern oregon coast - Weak high pressure over the water will give way to low pressure dropping down from the gulf of alaska, moving inland through Saturday. Front moves over the waters Friday morning through late Friday. Active weather persists through the weekend.

FXUS66 KPQR 021719 AAA AFDPQR

Area Forecast Discussion...UPDATED National Weather Service Portland OR 1019 AM PDT Thu May 2 2024

Updated aviation and marine discussion.

SYNOPSIS
Another system will bring rain and Cascade snow (above 4000 ft) this morning. Expect conditions to dry with some clearing skies by this afternoon. Heavier rain arrives Friday into Saturday, but we are not expecting any widespread hydrological concerns at this time. Cool, wet, unsettled weather likely continues through the middle of next week.

SHORT TERM
Now through Saturday Night...Mesoanalysis as of 245 AM PDT depicts a 1013 mb low pressure system centered off the north Oregon coast. This low is currently progressing southeast, bringing a band of light to moderate rainfall across northwest Oregon and southwest Washington. Based on webcams, snow is beginning to fall in the Cascades. The very marginal Winter Weather Advisory remains in effect for the North Oregon Cascades, and the Marion, Linn, and Lane County Cascades through 11 AM PDT today. Expect around 2-6 inches of snow this morning above 4000-4500 feet, with heavier snow above 5000-5500 feet.

For everyone else, the heaviest rain amounts this morning will be south of a line extending from Astoria-Portland-Hood River.
Locations such as the central Oregon coast, central Oregon Coast Range, and central/south Willamette Valley are forecast to receive an additional 0.25-0.40 inch of QPF this morning. Along and north of the Astoria-Portland-Hood River line, precip amounts will generally be less than two tenths of an inch. The bulk of the precipitation will end no later than mid-morning today (8-10 AM) as this system quickly exits and weakens to the southeast. Expect predominately dry conditions by this afternoon with a bit of sunshine as transient high pressure builds aloft.
This will allow today's afternoon high temps to climb into the 60s for most inland locations.

The more active weather arrives Friday afternoon as a much deeper trough drops out of the Gulf of Alaska and sends a stronger front across the area Friday into early Saturday.
Expect heavier rainfall to accompany this system as IVT values briefly max out around 250-400 kg/ms Friday evening, with precipitable water values around 1 inch running two standard deviations above normal by early May standards. There have been minimal changes to the QPF forecast, with 1-1.5 inches for the interior lowlands, and 1.5-2 inches for the coast and mountains from late Friday morning to Saturday afternoon. Winter weather impacts are not expected for the Cascade passes on Friday as snow levels will be rising above 7000 feet.

Fortunately, the system looks to move through rather quickly with rain tapering off to showers by Saturday evening as the low dives south towards the OR/CA border. Snow levels will drop back down to 3500-4500 feet by late Saturday morning, returning snow to the Cascade passes. The latest NBM suggests a 40-60% chance of 6 inches of snowfall or greater in a 24 hr period ending 5 AM Sunday. Another Winter Weather Advisory is starting to look more likely for Saturday.

Despite the impressive QPF amounts for this time of year, the fast progression of this system should help limit hydro concerns across the area. We could see a slight uptick in river levels, however, HEFS probabilistic guidance still keeps the chance of reaching action stage below 5-10% on all area rivers. That said, the system will still bear watching into the weekend given that area reservoirs are close to full and snow levels will be rising above 6500-7000 feet on Friday. If nothing else, we could certainly see some local ponding of water in prone areas from late Friday into early Saturday. -Alviz/CB


LONG TERM
Saturday through Wednesday...Expect an active, cool, and showery pattern to persist into the middle of next week as WPC ensemble clusters continue to show general agreement on some semblance of upper level troughing remaining over the Pacific Northwest through Wednesday. Do not see any signals for particularly notable QPF in any one period beyond Saturday, but area rivers will likely continue to run high for this time of year as episodic bouts of rain continue across the region.
Temperatures will continue to run a bit below normal, with daytime highs struggling to get out of the 50s through Wednesday. Will note that clusters do start to show a high pressure ridge building over the NE Pacific on Wednesday. If this ridge ends up moving eastward, then we could potentially see a pattern shift towards drier and warmer weather by late next week. -Alviz/CB

AVIATION
The front continues to push eastward with post-frontal showers and cumulus forming behind it. The main concern today is CIGs , though in reality they will have minimal impact. Looking at widespread VFR CIGs , with some lower level scattered clouds below 1,000 ft AGL through around 20Z. Those areas most impacted will be along the coast. Some portions of the Willamette Valley are still seeing IFR CIGs , but based off of satellite imagery, it looks like it should dissipate soon as winds increase. One thing to note though is that the northerly winds around KUAO and KSLE may keep the stubborn stratus in place. After 06Z Friday, the lower levels of the atmosphere moisten with radiational cooling. Models are suggesting a low dewpoint spread in the Willamette Valley and the central Oregon Coast. Based on high resolution models, there are increasing chances for MVFR to even IFR conditions after 12Z Friday.

The next frontal system arrives after this next TAF package, but with the onset, because it is a cooler front, will see strong winds, especially along the coast and through the Columbia River Gorge.

Notes: The ASOS at KTTD is only available via the dial in option.
There is no estimated time of full repair and restoration for this location.

PDX AND APPROACHES...Mainly VFR with scattered IFR clouds through 20Z Thursday. Will see minimal changes today aside from a slow wind shift from the north to the south through the day. The main concern is whether or not the clouds will lower overnight. Based on some model outputs, the dewpoint depression falls to near zero after 09Z Friday, while others keep conditions dry in the lower atmosphere. Cannot rule out low stratus though as there is a 30% chance of IFR CIGs and VIS after 12Z Friday. -Muessle

MARINE
Low pressure and associated front continue to shift eastward today. The low will continue to weaken today as will winds. High pressure builds offshore resulting in northerly wind developing later in the day.

The next impactful event arrives early Friday. This low pressure system and associated front appear to be much more robust, so have issued a Small Craft Advisory for the outer zones, PZZZ 271,272,273, from Friday morning through early evening with gusts 20 to 30 kt. Lower forecast confidence for the inner zones with a 20-50 percent chance for gusts above 21 kt. Will see which way models trend to decide on issuing an advisory or not.

Seas starting out around 4 ft this morning but looks to remain below 10 ft through the weekend and early next week. -MH

PQR WATCHES/WARNINGS/ADVISORIES
OR...Winter Weather Advisory until 11 AM PDT this morning for ORZ126-127.
Winter Weather Advisory above 4500 feet until 11 AM PDT this morning for ORZ128.
WA...None.
PZ...Small Craft Advisory from 8 AM to 8 PM PDT Friday for PZZ271>273.

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