Sunrise 5:06 AM   Sunset 10:45 PM Moonrise 12:04 PM   Moonset 2:33 AM

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PKZ780 SEguam To Adak Bering Side Out To 15 Nm- 209 Pm Akdt Wed May 15 2024
.small craft advisory tonight - .
Tonight - W wind 20 kt. Seas 8 ft.Thu - Variable wind 10 kt. Seas 6 ft.Thu night - S wind 15 kt. Seas 5 ft.Fri - W wind 15 kt. Seas 4 ft.Fri night - Variable wind 10 kt. Seas 3 ft.Sat - SE wind 15 kt. Seas 3 ft.Sun through Mon - S wind 15 kt. Seas 4 ft.

PKZ700
No data

FXAK68 PAFC 151311 AFDAFC

Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 511 AM AKDT Wed May 15 2024

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/Today through Friday night)...

A high amplitude upper level ridge is building into Southcentral from the west, leading to warming temperatures aloft and a more stable atmosphere (as seen in the 12Z Anchorage sounding). Skies have cleared out across much of Southcentral, with some localized areas of mostly mid level clouds. There are some signs in satellite imagery of patchy low clouds and fog along the Gulf coast and into Prince William Sound. Areas of low clouds can also be found on Kodiak Island. Under clear skies, temperatures have once again dropped into the 20s and 30s - as the low level airmass remains quite chilly.

The upper level ridge will build directly overhead of Southcentral today, then very slowly shift eastward and weaken through Friday, lingering along the ALCAN border and the Copper River Basin. At the surface, high pressure will build northward across the Gulf to Southcentral today. Synoptic onshore flow will combine with warm temperatures inland to induce strong sea breezes along all coasts today. The winds will develop early, which will provide a cooling influence on temperatures in coastal communities.

As the ridge slides eastward, a long-wave trough over the Bering will approach the western Gulf along with a weakening cold front.
This will bring some very light rain to southern and eastern portions of Kodiak Island by late tonight, spreading north to the Kenai Peninsula on Thursday. Models solutions, which had varied significantly in previous days with track of individual short-waves, are now in much better agreement. Guidance depicts a negatively tilted short-wave moving into the western Gulf Thursday afternoon, forming a weak low in the northwest Gulf Thursday night, then tracking the trough and low eastward across the Gulf on Friday. As a result, precipitation likely won't make it further north than the Kenai Peninsula, where very light rain (and mountain snow) is likely Thursday through Friday morning.

After today's sunshine and warm temperatures inland, increasing clouds will lead to cooler temperatures Thursday through Friday.
The one exception will be the Copper River Basin, which will remain warmer under the influence of the upper ridge. Instability will be weak, but with some breaks of sun on Friday, there could be isolated convection. Even with that, most of the region (other than the Kenai Peninsula) will remain precipitation free for the next few days.

-SEB

.SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA AND THE ALEUTIANS (Days 1 through 3)...

The front of a Kamchatka low is beginning to impact the west coast of Alaska, producing widespread rain and snow showers for the region. Gusty winds both offshore and inland are expected through tonight, with the strongest gusts of 35-45 mph occurring near Mekoryuk and Toksook Bay over the next few hours. Strong southwesterly flow is expected over this time, but with below freezing air at the 850 mb level many areas at lower elevations may see a mix of rain and snow in the morning hours and rain in the afternoon. Winds will quickly die off tomorrow morning with most areas along Southwest getting calm south or southwest winds.

In addition to the low impacting Southwest, a couple of shortwaves will pass by the western and central Aleutians over the next couple days. The first system will enter Wednesday night, giving the western Aleutians a quick opportunity for precipitation amounts from a trace to 0.15" and small craft force gusts through Thursday afternoon. The next wave will enter Friday morning and persist through at least Friday afternoon. There are still uncertainties in the intensity and track of this wave amongst the most recent model runs. The interaction of this wave with a future developing upper level low in the northern Bering will play a role in its impact on the Aleutians.

-BS

.LONG TERM FORECAST (Days 4 through 7: Friday through Tuesday)...

The long term forecast for the Southern Alaska will begin with a ridge over the Gulf of Alaska sliding east as a shortwave trough rounds the base of a longwave upper-level trough situated over the Bering and moves over Southwest Alaska. Model agreement regarding the associated frontal boundary moving across the Aleutians is mild, as a few of the models are slightly stronger than others.
However, the timing regarding this system is fairly well agreed upon, with this system then exiting to the east late Saturday.

Sunday may offer a reprieve from any extensive cloud cover and/or shower activity across the Southern Mainland. But, again, all models are struggling with the track of various shortwaves embedded within the longwave trough. While guidance shows a ridge trying to build north from the North Pacific and western Gulf, the GFS is advertising a quicker breakdown of the ridge, a common and usually incorrect bias. This solution is still possible, and would place the entirety of the Southern Mainland on the back side of the ridge with the resultant southwesterly flow lending to a more unsettled pattern with various waves moving along the Aleutian Chain and across the AKPen and Kodiak Island. The result would be more cloud cover and chances for rain across the region.
Given the consistency of the latest GFS runs and a trend of the EC and GEM ensembles progressively leaning more toward the GFS recently, the long term is weighted more toward the stronger ridge solution.

For the Aleutians and Bering, the longwave trough situated over the region will like keep conditions cool and unsettled through the long term. Any ridging between storm systems would be brief, with the best chance for high pressure over the Bering late Friday into Saturday. Any warmer air associated with the ridge, though, would likely result in widespread stratus and fog due to the warmer air riding over the cold open waters. By the beginning of next week, uncertainty between the models grows with regards to a low pressure system entering the western Bering Sea, and the subsequent progression of the system across the Aleutians, is currently high. It is looking like the pattern of training troughs across the Bering will continue into the next work week.

-TM/CL

AVIATION

PANC...VFR conditions will prevail. The combination of warm temperatures inland and increasing southerly winds up Cook Inlet will lead to a robust southwesterly sea breeze this aft/eve.
There could even be a few gusts as the strongest push of winds reaches Anchorage between about 00Z and 04Z.

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Atka Pass
Click for Map
Wed -- 01:06 AM HDT     4.33 feet High Tide
Wed -- 02:49 AM HDT     First Quarter
Wed -- 04:33 AM HDT     Moonset
Wed -- 05:51 AM HDT     3.48 feet Low Tide
Wed -- 06:46 AM HDT     Sunrise
Wed -- 08:16 AM HDT     3.49 feet High Tide
Wed -- 02:03 PM HDT     Moonrise
Wed -- 04:02 PM HDT     -0.06 feet Low Tide
Wed -- 10:30 PM HDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION

Atka Pass, east end, Atka Island, Alaska, Tide feet

Bechevin Bay
Click for Map
Wed -- 02:24 AM HDT     3.32 feet High Tide
Wed -- 02:49 AM HDT     First Quarter
Wed -- 04:32 AM HDT     Moonset
Wed -- 06:45 AM HDT     Sunrise
Wed -- 08:05 AM HDT     2.66 feet Low Tide
Wed -- 09:34 AM HDT     2.68 feet High Tide
Wed -- 02:02 PM HDT     Moonrise
Wed -- 06:16 PM HDT     -0.05 feet Low Tide
Wed -- 10:29 PM HDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION

Bechevin Bay, Atka Island, Alaska, Tide feet

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