Marine Weather and Tide Forecast for Unalaska, AK

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

An unseasonably strong storm system is tracking northward across the central Bering Sea this afternoon, passing west of the Pribilof Islands. The low will soon fully occlude, meaning it will be at its strongest over the next few hours or so. A strong frontal system is spreading out north and east across the bering Sea and toward the Southwest Alaska coast. Widespread rain and strong and gusty winds are being observed across the region. Of particular note, southerly gap winds across the Eastern Aleutians and southern Alaska Peninsula have reached 50 to 55 kt (57 to 63 mph). The weather started out sunny and warm across interior Southwest AK today, but clouds are increasing as the frontal system nears the SW coast.

A strong upper level jet stream and short-wave trough will drive the surface front onshore of Southwest AK this evening, then inland overnight through early Monday morning. This will lead to widespread gusty winds and rain, moderate at time. The front will move fairly quickly, so the worst conditions will generally won't last longer than about 6 hours. A High Surf Advisory remains in effect and on track for high water and potential beach erosion along the Kuskokwim Delta coast during the high tidal cycle on Monday. A combination of cold unstable conditions behind the front and upper level short-waves rounding the low center will lead to showers and gusty winds across the region through Monday.

While the current low weakens over the central Bering Sea Monday through Wednesday, a couple other lows will approach from the Pacific. The first will be a weak low approaching the central Aleutians on Tuesday, with an uptick in winds and another round of rain for the Central to Eastern Aleutians Tuesday through Tuesday night. A deeper low will approach the Alaska Peninsula Tuesday night through Wednesday, with a leading frontal system lifting northward into Bristol Bay. Expect strong and gusty easterly winds across the Alaska Peninsula and Bristol Bay along with areas of rain.

-SEB

.LONG TERM FORECAST (Days 4 through 7: Thursday through Sunday)...

The long-term period looks to stay mainly active from the Bering Sea, The Gulf of Alaska, and the southern mainland. A broad trough across the Bering Sea will extend eastward into the Gulf Thursday and into the weekend as the trough digs southward with time.
While there is good agreement synoptically with upper-level pattern, there are still questions and uncertainties regarding surface features. There is lots of ensemble spread with regards to surface low pressure centers Thursday through Sunday across the Bering Sea and Gulf. This will have implications on both the precipitation forecast as well as the wind forecast across both areas and locations that are inland. However, there is reasonable agreement between operational guidance and the ensemble suites that upper- level ridging will develop across the Western Aleutians/western Bering Sea Saturday and Sunday.

AVIATION

PANC...VFR conditions will likely prevail through early Monday morning. Rain will spread up Cook Inlet and the Kenai Peninsula Monday morning with increasing rain chances after 12Z. The Turnagain Arm wind likely clips the terminal Monday morning with southeasterly winds accompanied by showers, which may cause a drop to MVFR conditions. Rain showers expected much of the day Monday then gradually dissipating Monday evening.