textproduct: Juneau

SYNOPSIS

Key Messages:

- Winds and precip will diminishing tonight, but onshore flow continues.

- The wet and active pattern will continue for Tuesday and beyond as multiple gale to potentially storm force fronts and lows push through the Gulf and bring impacts to the panhandle.

LONG TERM.../Tuesday through Thursday night/

An active Fall pattern continues through the extended forecast, with short breaks of dry conditions in between passing systems. Maritime interests should remain aware of Gale force fronts pushing across the Gulf and along the coast on Tuesday and Thursday.

A long wave upper level trough over the Aleutian Chain swings the first of many fronts across the Gulf through Tuesday, with widespread sustained Gale force winds 35 to 45 kts and storm force gusts up to 55 kts across the Gulf and along the coast from Cape Decision northward to Cape Suckling through the day. Overland, strong winds remain possible across the central and southern panhandle given current forecast orientation of the front with gusts u for Prince of Wales, Ketchikan, and Metlakatla by late Tueday night into Wednesday afternoon. By Wednesday night, a separate, but stronger low develops in the northern Pacific as it deepens to ~970mb by Thursday morning, and moves into the southern Gulf of Alaska. This low will swing a strong front across the gulf through Thursday, bringing another round of sustained Gale force winds 35 to 45 kts and storm force gusts up to 55 kts across the Gulf and along the coast from Dixon Entrance northward to the Fairweather Grounds through the day. Strongest overlands winds once again focused across the southern panhandle, however albeit less forecast confidence on location and expected gusts, but would not be surprised to see gusts up to 35 mph by Thursday evening for Ketchikan and Metlakatla (looking at you Yellow Hill).

As of now, no significant QPF concerns with this system given how fast each front is expected to push through. Periods of moderate to heavy rain are expected, but not expecting a long duration rainfall threat. Current rainfall amounts with each front is around 0.5-1.5" across the northern and central panhandle, 1-2" for the southern panhandle.

AVIATION.../Through Monday afternoon/

As a meso-low approaches the outer coast and the southern front moves inland, moderate to heavy rain and gusty winds are impacting many sites. Peak gusts have reached 35- 40 kt across Prince of Wales, Ketchikan, and Metlakatla, and are expected to trend down this evening. LLWS remains a concern near southern terminals this afternoon, though winds in the SFC-2,000 ft layer will diminish significantly by 03Z. Flight conditions in these areas have largely transitioned from MVFR to VFR, except near Ketchikan. Central sites are trending down to CIGs of 1,500-3,000 ft with localized VSBY drops to 3-4 SM in heavier bouts of rain. Conditions will improve overnight as the system lifts northeast, with precipitation tapering to lighter showers from south to north. North of Frederick Sound, CIGs remain between 2,800 and 4,800 ft and will likely stay high-end MVFR to low-end VFR through Monday afternoon.

MARINE

Outside (Gulf and Coastal Waters): An area of low pressure Southeast of Kodiak Island has been sending a front through the Panhandle today. Behind the front, expect winds and seas to decrease through late tonight. A mesolow currently near Cape Decision Tuesday, a stronger front will approach the area, and bring gale force winds into the Gulf of Alaska. There is also potential for storm force winds due to a barrier jet forming between Icy Cape and Cape Suckling.

Inside (Inner Channels): Along a front impacting SE Alaska, a mesolow expected to move NE near Baranof Island is expected to increase wind speeds for Chatham Strait and Southern Stephens Passage. As it moves into the inner channels, expect the system to dissipate. Early Monday morning, a secondary mesolow in the North Pacific will bring stronger winds to the Southern inner channels. Based on the track of the low, it may bring gale force winds into Clarence Strait.

Based on current guidance, the strongest winds should stay in Dixon Entrance. However, the track will be closely monitored. For the Northern inner channels, winds are expected to not be as strong, as the low SE of Kodiak Island will weaken. Another area of low pressure will move in from the West on Tuesday, and this is expected to increase winds again Tuesday. Late Tuesday into Wednesday, the strongest gale force winds are again expected in Clarence Strait.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Winter Storm Warning until 3 PM AKST this afternoon for AKZ318. Wind Advisory until 5 PM AKST this afternoon for AKZ330-332. MARINE...Gale Warning for PKZ036. Small Craft Advisory for PKZ022-031-033>035-641>644-651-652- 661>664-671-672.