textproduct: Juneau

SYNOPSIS

Key Messages:

- The wet and active pattern continues through the week as multiple fronts push into the panhandle, bringing periods of moderate to heavy rainfall and strong winds.

- Maritime interests should remain aware of multiple Gale force fronts with potential for Storm Force wind gusts across the Gulf and along the coast on Tuesday, Thursday, and into the weekend.

- Light snow possible along northern highways. Little to no snow for the Haines Highway, with 2 to 5 inches through Tuesday night near White Pass.

LONG TERM.../Wednesday through Saturday/

An active Fall pattern continues through the extended forecast. Maritime interests should remain aware of multiple Gale force fronts pushing across the Gulf and along the SEAK coast by Thursday and into the weekend.

We pick up the extended forecast on Wednesday morning with the remnants of the Tuesday system pushing out of SEAK, scattered showers and diminishing winds briefly through the afternoon. However, Wednesday will be the last "quiet" day of the extended period as multiple strong low pressure systems that will traverse the North Pacific and then into the Gulf for the end of the week and into the weekend. Some variance on timing , but still thinking by Wednesday night a strong low develops in the northern Pacific and deepens to ~970mb by Thursday morning as it moves into the southern Gulf of Alaska. This low will swing a strong occluding 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 by Thursday afternoon into Thursday night. Strong overland winds up to 45 mph focused across the southern panhandle by Tuesday afternoon, primarily Prince of Wales, Ketchikan, and Annette Island so will need to keep on potential Wind Advisory Issuance moving into the middle part of the week. This low and its attendant front continue to push into the NE Gulf coast through Friday afternoon with scattered,off and on showers becoming more prevalent into Friday night, so there is a potential brief break in the widespread rainfall Friday night, albeit not high confidence.

Total rainfall amounts from the front on Thursday into Friday total ~0.5 to 1.5 inches across the northern and central panhandle, and ~1.5 to 2.5 inches of rain for the southern panhandle. With the follow up systems from Friday night into Saturday night, rainfall amounts will once again be around the same, maybe a bit higher given influx of available moisture tap. All in all, the totals from Thursday through Saturday night, around 72 hours, are around 2 to 4 inches for the northern and central panhandle, 3 to 5 inches across the southern areas. Give persistent warmer southerly winds across the panhandle, any snowfall should remain at the upper elevations of the Klondike Highway near White Pass and Haines Border Crossing. The further we get into the extended the less forecast confidence in placement of developing systems, but general consensus is that the pattern remains active with yet another surface low developing in the Gulf of Alaska on the periphery of a deep long wave trough situated across the Gulf into latter half of the weekend.

AVIATION

Rain has almost entirely exited the northern panhandle, but some interior sites in the central and southern panhandle continue to experience showers associated with a shortwave moving to the north. Things will quiet down during the overnight period, with overcast skies likely holding, but CIGs raising to AoA 3kft for almost every TAF site, providing largely VFR conditions in the overnight. On Tuesday a strong front will approach from the western Gulf, strengthening the wind field starting in the north with PAYA and moving south and east throughout the day and evening. The return of precipitation by 04/00Z on Tuesday will likely be limited to Yakutat and coastal locations.

MARINE

Outside (Gulf and Coastal Waters: Due to an area of low pressure moving NE from the N Pacific, the strongest winds today have been in the vicinity of the low in the North Pacific. Our next front is currently moving NE through the Gulf of Alaska, and is expected to bring gale force winds in the Gulf of Alaska tonight into Tuesday. From Icy Cape to Suckling, sustained storm force winds are possible due to the formation of a barrier jet late Tuesday into early Wednesday. However, there is still model disagreement on exactly how strong the sustained winds will be. With strong winds aloft (+50 kts), storm force gusts are expected as the front moves toward the barrier jet. As that front dissipates Wednesday, another low pressure system will move in the Gulf Thursday morning. The long range marine weather forecast also appears to be quite active in the Gulf of Alaska, with several fronts expected to move through.

Inside (Inner Channels): A mesolow near Haida Gwaii has brought stronger winds from Dixon Entrance into Clarence Strait. As the low dissipates this evening, expect winds to decrease for the Southern Panhandle. With the low increasing winds for the Southern Panhandle, there have been generally Northerly winds for the Northern inner channels. A gale force front in the Gulf Tuesday will lead to elevated winds and seas through the inner channels. A mesolow may form along the front Wednesday, and this is a possibility that needs to be closely monitored, as there is still disagreements in the model guidance on the exact progression. If a mesolow can form, expect elevated winds in its vicinity. As of now, if any develops, it would likely be near Prince of Wales Island, and may impact Southern Chatham Strait or Western Sumner Strait.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Gale Warning for PKZ642>644-651-652-661>664-671-672. Small Craft Advisory for PKZ021-022-032>036-053-641.