Marine Weather and Tide Forecast for Clam Gulch, AK

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

Radar imagery this morning shows numerous scattered showers persisting across Southwest Alaska as several perturbations embedded within weak upper level troughing continue to push east ahead of a transient ridge in the central Bering Sea. Further west, a look at satellite this morning shows a deepening complex low in the North Pacific as a digging shortwave phases with a lifting North Pacific low. These two features will consolidate by this afternoon, allowing for the storm to rapidly strengthen in the left exit region of a 160 kt upper level jet streak in the North Pacific while its gale to storm force front lifts north into the Bering.

Widespread rainfall and gusty winds will continue to push into the Central Aleutians through this morning, bringing high end gale to storm force winds. The low briefly stalls to the south of the Central Aleutians this afternoon as the central surface pressure bottoms out at around 960 mb before continuing on its track along the Aleutian Chain and Alaska Peninsula through Wednesday. The front will bring similarly strong gale to storm force winds and rain along the Eastern Aleutians through this afternoon and along the AKPen this evening through Wednesday morning. Strong southeasterly wind gusts up to 65 mph will be possible through favored gaps in the Eastern Aleutians and Alaska Peninsula.

Shower activity over Southwest Alaska should begin to decrease this afternoon as a weak and quick moving ridge moves over the region ahead of the approaching front. Southerly winds of 15 to 20 mph will begin to pick up this afternoon ahead of the front. The front eventually pushes into the Southwest Mainland Tuesday night into early Wednesday morning, bringing strong easterly winds of 30 to 35 mph with gusts to 45 mph across Bristol Bay and the Kuskokwim Delta through Wednesday afternoon. Easterly winds are not as favorable for coastal flooding, so coastal communities will likely be spared from significant coastal flooding as the low affects the region. Elevated water levels may still be possible during high tide cycles. Strong winds will be accompanied by light to moderate rainfall, with around a half inch of rain expected for the Kuskokwim Delta Coast through Wednesday night.

Northwest winds with gale force gusts and showery weather on the back side of the low will continue for the Eastern Aleutians and AKPen through Thursday morning as the low tracks towards the Gulf.
This northwest flow and cold air advection behind the low will bring a change of airmass to the Bering Sea and Southwest Alaska late this week into the weekend, with low temperatures falling to around freezing by Friday morning.

-JH

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

The extended forecast for the region indicates a continuing active weather pattern, dominated by a series of deep and fast- moving low-pressure systems tracking from the Aleutians towards the mainland. The next significant system will approach mid-week and could split into two centers: one moving into the Gulf of Alaska and the other into heading northeast towards Southwestern Alaska. This splitting may slightly diminish the threat of the highest for the southern mainland, but the system will still bring moderate to heavy rainfall across the Alaska Peninsula and the southern coast. Later in the week, an area of low pressure developing over the Gulf of alaska will enhance precipitation for Southcentral Alaska and Prince William Sound. Some lighter rain and high-elevation snow are also expected to reach farther north.

We are watching for the potential for another powerful cyclone to arrive near the Aleutians by next weekend. Current model consensus suggests this system carries an increasing threat for high winds across the entire length of the Aleutians, potentially extending into Southcentral Alaska. Given the persistent nature of these systems, the overall airflow across the state is expected to remain predominately from the southwest.

-DD

AVIATION

PANC...Light rain showers will be possible at the terminal early this morning, with potential for ceilings to drop to MVFR intermittently. Showers clear out and ceilings lift but generally remain below 5000 ft through midday. A slight chance of showers will persist through the afternoon hours, but generally expecting VFR conditions to return with ceilings lifting above 5000 ft.
Light southerly winds persist through midnight. Then, there is potential for a southeasterly Turnagain Arm wind to clip the terminal overnight, with gusts to 20 kt possible. The Turnagain Arm wind turns down inlet through Wednesday morning, with winds most likely to be light out of the north.

Quesada