Marine Weather and Tide Forecast for Twin Hills, AK

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

As of this afternoon, a broad surface trough anchors two distinct areas of low pressure - with one mostly stationary and just south of Sand Point and Chignik with another situated over the Bristol Bay waters. Radar returns depict widespread showers across Southwest Alaska and the Alaska Peninsula pivoting around the northern most area of low pressure. Instability has been limited due to temperatures stuck in the 50s and cloud cover for much of the region, but there has been enough instability/warming in the Kuskokwim Valley to touch off quite a few lightning strikes this afternoon. This activity is very isolated in nature and should be fairly short lived through the rest of the evening.

Looking westward, vertically stacked high pressure is centered over the Western Aleutians with ridging extending eastward over the Bering. The surface pressure gradient between this ridging and the troughing across Southwest Alaska has formed a wide swath of stout northerly 25 knot winds that have been moving across the Pribilof Islands today. Northerly gap winds across the Aleutian Chain have been elevated as well and will most likely stay that way through tomorrow afternoon.

With the troughing not moving much over the next 12 to 16 hours, rain shower activity will persist for Southwest Alaska through Monday morning. There is high confidence of an additional tenth to a quarter inch of rainfall, mainly west of the Kuskokwim Valley through Monday morning. The global models show that the aforementioned ridge begins to move eastward Monday afternoon, which will essentially cause the low south of Sand Point and Chignik to gain momentum and move eastward with time/exit the region. There is good agreement among the global and hi-res models that much of the rain shower coverage further decreases Tuesday morning across Southwest Alaska, with only a chance of showers expected Tuesday afternoon with the surface low moving into the Gulf.

As the low exits, the ridging moves eastward and takes control of the west-central Bering through Wednesday morning, keeping fog and low stratus in the Bering through the rest of the short term.

-AM



.LONG TERM FORECAST (Days 4 through 7)...

Southcentral: An upper level ridge over the Eastern Gulf of Alaska moves eastward and a low south of Kodiak Island gradually migrates northeastward. These will bring southerly flow to Southcentral and Kodiak Island resulting in steady rain for Prince William Sound and Eastern Alaska Peninsula Wednesday and Thursday. The dry trend further inland Wednesday into Friday remains 60% likely as models persistently show a cutoff of moisture in the Anchorage Bowl, Western Kenai Peninsula and Mat- Su Valleys.

As the week progresses though, the chance for thunderstorms and rain showers returns for the Copper River Basin Thursday and Friday. This chance spreads westward into the Susitna Valley next Saturday and Sunday. Though confidence in both placement and exact timing of these weather elements from Thursday into next weekend is low, the deep southerly push of moisture and the introduction of a westerly-moving ridge from the Yukon is an indicator of end of week / weekend thunderstorms and showers to the area. The chance of occurrence over the four days for both the Copper River Basin and the Susitna Valley though increases as high pressure in the Yukon strengthens and brings the ridge farther west.

Southwest, Bering Sea and the Aleutians: A weak low moves across the Bering Sea and over the Mainland bringing showers and cloudy conditions mid-week. Fog and decreasing precipitation are expected next weekend as high pressure builds in the Bering Sea.

-DJ


AVIATION

PANC...Expect southeast winds to continue gusting near 40 kts over the terminal through this afternoon and slowly diminish this evening into the overnight hours. The strong southeast flow will also keep the majority of rain confined to the coast and keep the terminal mostly dry. Therefore, VFR conditions are expected to continue throughout the TAF period. Southeast Turnagain Arm winds look to clip the terminal once again Monday afternoon. However, winds Monday afternoon are not expected to be nearly as strong as today's winds.