Marine Weather and Tide Forecast for Port Lions, AK

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

**Key Message: A Winter Storm Watch has been issued for the Kuskokwim Delta and Kuskokwim Valley from late tonight through Tuesday afternoon for up to 2" of snowfall and up to 0.20" of ice accumulation.**

A large system in the North Pacific remains south of the Aleutian Chain with a gale force front that continues north across the Southwest mainland. Gale force winds will continue westward through Bristol Bay and south across the Bering Sea, diminishing overnight into Sunday near the coastal mainland. Precipitation from this system will lift into Bristol Bay and inland north of Dillingham by this afternoon. The Y-K Delta is expected to remain drier due to downsloping until early Sunday. Precipitation is then expected to continue for most of Southwest Alaska through Monday.

For areas under the Winter Storm Watch, particularly farther inland across the Kuskokwim Delta where surface temperatures are lower, freezing rain will likely persist through late Monday before transitioning back to a rain/snow mix. Ice accumulation is expected to remain light, at two tenths of an inch, and less than 2 inches of snow through the forecast period.

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

Uncertainty continues to be an issue in the long term. A North Pacific low is projected to track into the Bering Sea with the leading front bringing widespread precipitation and gale force to storm force winds from the northeast direction across much of the Bering Sea. Winds along the western periphery of the low will become northerly as it crosses the western Aleutians.
Precipitation type is the main challenge for the mainland for the early part of next week as cool temperatures remain at the surface and warmer air filters across the region aloft. Although the low weakens in the southern Bering, it is not entirely clear how long this forecast challenge will persist through the rest of the week.
This system appears to bring a prolonged pattern, especially for southwest Alaska with strong winds, precipitation, and warm southerly air moving over cool northerly air. For the Gulf and Southcentral, waves of surface lows and fronts will transit the Gulf, but some uncertainty remains to its strength and trajectory into the northern Gulf or eastern Gulf. At the least, expect showers to continue for coastal areas with less clarity for the long term weather conditions farther inland. Toward the last half of the week though, a strong front moves into the western Bering Sea from a Kamchatka low. Storm force gusts seem more likely along the front but may be stunted progress as it bumps into a narrow area of high pressure in the central Aleutians and Bering Sea. An upper level blocking pattern seems possible with high pressure to the north and areas of low pressure with embedded disturbances transiting south and along the Aleutians. Breezy gap winds across Southcentral will be possible for the latter half of the week.

AVIATION

PANC...VFR conditions with ceilings above 5000 ft and light northerly winds will persist through the TAF period. Precipitation chances increase this afternoon with the arrival of another frontal system. A mix of freezing rain and snow is possible initially, with ceilings and visibility dropping to MVFR.
Temperatures gradually increase through the evening and overnight, so lingering precipitation eventually turns over to all rain. A light glaze to a tenth of an inch of ice is possible. Ceilings and visibility improve back to VFR after midnight with diminishing precipitation. Another round of light precipitation is possible on Sunday, with more uncertain timing. This is expected to fall as a mix of rain and snow with minimal chances for freezing rain.
Ceilings and visibility potentially drop back to MVFR during heavier precipitation, especially if snow.

Quesada