Marine Weather and Tide Forecast for Whittier, AK

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3)...

KEY MESSAGES...

1) A High Wind Warning remains in effect for Adak and Atka until noon today, and a Wind Advisory remains in effect for Unalaska through 9PM this evening.

2) The Winter Weather Advisory remains in effect for the Pribilof Islands through 9PM this evening.

3) Heavy snow/blowing snow expected for coastal Southwest Alaska and the Kuskokwim Delta, with blizzard conditions expected along the Kuskokwim Delta Coast.

The large Bering Sea low is currently situated west of the Pribilof Islands and will continue making its way northeastward toward Nunivak Island/Southwest Coast over the next couple of days. The associated front is expected to reach the Southwest Coast early this morning, bringing rounds of heavy snow/blowing snow, with blizzard conditions highly likely along the Kuskokwim Delta Coast, with increasing chances for blizzard conditions in the Western Capes. The front is expected to work its way inland and weaken through today, spreading snow further inland. Some warmer air is expected to filter in behind the front, bringing temperatures up into the upper 20's and low 30's, though mostly remaining at or below freezing for most areas of Southwest.
Regardless of warming temperatures, snow showers are expected to continue behind the front, persisting (but lighter overall)
through Wednesday morning. Winds will gradually diminish but are expected to remain gusty through Wednesday morning as well, resulting in brief periods of localized blowing snow at times. Due to the amount of sea ice into the Bering and shorefast ice along the coast, the threat of coastal impacts is minimal at this time.

Winds across the Bering Sea will remain gusty today as the low tracks east/northeast. Strong winds ranging from 80 to 90 mph across Adak and Atka expected this morning will begin diminishing this afternoon. Similarly, wind gusts as high as 70 mph are possible along the Eastern Aleutians, including Unalaska through much of today into this evening. Additionally, strong south- southeasterly winds pushing over the Pribilofs, combined with persistent snowfall, will continue into through this evening. The heaviest snow is expected to taper off later this morning, but gusty winds and lighter falling snow may continue to result in reduced visibilities in blowing snow.

.LONG TERM FORECAST (Days 4 through 7 - Friday through Monday)...

By Friday, a weak but well agreed low pressure system will be stationed over the northern Gulf of Alaska, likely promoting unsettled conditions with onshore easterly flow into the Western Prince William Sound and precipitation. A similarly weak ridge over the Southern Alaska Peninsula will be weakening further and retreating to the northern Pacific, making way for the next system to enter the Bering. A strong low over the Kamchatka Peninsula Friday morning will have pushed a fairly strong front into the Central Bering and Aleutians. Agreement is mixed on whether or not a subsequent low will form along the triple-point of this front, which would work to increase it's effects across the region. By Friday morning, the front will be sweeping a large swath of strong southerly winds across much of the Chain, and by later Friday morning, pushing a new precipitation pattern into Southwest Alaska. By Friday afternoon, agreement remains strong that the Kamchatka low shifts into the Northern Bering, allowing the front to orient favorably for strong onshore winds into Southwest Alaska as well as continued precipitation across the area.

Uncertainty arises on Saturday with the potential for smaller lows to move through the Bering. These would up winds and precipitation chances for wherever they move over. Uncertainty for Southcentral is a little better, with a low forming somewhere in the northern Gulf, allowing for snowfall for the coast and potentially inland as well. The picture will become more clear overtime as guidance gets a better feel for the forecast. By Sunday morning, agreement degrades further with some solutions bringing the ridge back in over the Southern Alaska Peninsula and another potent low moving near the Kamchatka Peninsula. Another, slower front may be entering the Western Bering and Aleutians near Shemya by Monday morning, with Southwest Alaska to shift back into a more benign inactive pattern.

-CL

AVIATION

PANC...The persistent stratus deck is beginning to erode over the terminal as drier air works into the region along with a light northwesterly wind. A FEW to SCT cloud deck below 1,000ft is also possible over the terminal through mid-morning. A potent frontal system moves into the area later this morning with LLWS developing as southeasterly wind aloft increase but a northerly wind holds over the terminal. Light snow will also develop over the terminal by mid-morning, with vis and cig lowering to MVFR. The increasing southeasterly winds aloft, however, will act to mitigate snowfall from around noon through late afternoon. Steadier snow then returns, along with IFR conditions, as the cross-barrier winds subside. Southerly surface winds then increase in the wake of the front tonight. Conditions slowly improve by Wednesday morning; however, bands of snow showers may result in periodic MVFR conditions.