Marine Weather and Tide Forecast for Kodiak Station, AK

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

The overall forecast remains on track. The main features to watch will be a low pressure system pushing into the Aleutians west of Adak, a ridge of high pressure lingering over the Bering Sea, and a North Pacific low moving into the Alaska Peninsula on Friday. As such, generally expect low clouds and fog across much of the Bering Sea and Aleutian Islands, with rain and sustained winds up to about 30-40 mph along the far western Aleutians and Alaska Peninsula. For Southwest Alaska, mainly clear and warming up under the influence of the ridge, with a chance of afternoon/evening rain showers and thunderstorms in the interior for Thursday and Friday. No major hazards are anticipated.

Diving into the details... as mentioned with the previous forecast discussion, a major forecast challenge over the coming days will be the extent and thickness of fog (as low as 1/4 to 1 mile at times) along the Bering Sea. The general weather pattern is supportive of widespread low clouds and fog, but with a scarcity of good observations across the Bering Sea, it's difficult to determine just how thick the fog is or will be. As such, have leaned more aggressive with the fog forecast, and towards thicker and more widespread fog than may actually be the case. On land (Aleutian and Pribilof Islands, Alaska Peninsula, Southwest coast), daytime heating will likely mix out the fog in the late morning to early afternoon, though timing is uncertain. At the end of the day, fog and low stratus behavior is highly dependent on smaller-scale dynamics that are difficult for weather models to represent, which makes the forecast challenging.

The other aspect of the forecast we'll be monitoring is thunderstorm potential on Thursday and Friday afternoons. The warming trend in the interior late this week will promote a thermally unstable environment, which will be favorable for the development of afternoon convection and perhaps even thunderstorms. The thing to watch will be upper level shortwaves moving through Southwest Alaska, which will influence where potential thunderstorms form and where they move. Overall, the upper level forcing for these two days looks fairly weak and chaotic, which suggests that developing convection may not be particularly robust or lead to very many lightning strikes. The trick will be to see how poorer upper level forcing balances out with fairly good low-level instability.

-KC

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

An upper level ridge over the eastern Gulf will remain nearly stationary through Sunday and then move eastward by Monday. This is important as it blocks an originating Pacific Low from going into the eastern Gulf, which will bring showers for Southwest Alaska and the eastern Aleutians through Tuesday. The combination of the anticyclonic flow aloft from the ridge and cyclonic flow from the low pressure system will enhance southerly flow ushering in warm and moist air into the northern and western Gulf coast.
This is expected to bring precipitation to Southcentral Alaska, the Alaska Peninsula, and Kodiak Island. There is high confidence that there will be periods of heavy rain for Kodiak Island through Prince William Sound Saturday into Sunday. Lingering showers are possible Monday through Tuesday as the southerly enhanced flow shuts off.
Forecast confidence is low for the western Aleutians.

-SS


AVIATION

PANC...VFR conditions will generally prevail through the TAF period. While most of the shower activity is over, there is still a chance for an occasional shower through the night. For tomorrow, most of the shower activity is expected to be over the mountains and not out by the airport. Winds will vary throughout today and then turn southerly this evening into Wednesday. Speeds are expected to remain less than 10 kts.