textproduct: Juneau

SYNOPSIS

Key Messages:

- A shortwave is pushing into southern panhandle through the afternoon, with parts of the northern and central panhandle seeing breaks in the active weather.

- Additional shortwaves pass through SEAK through Monday, bringing more rain and breezy winds to the panhandle.

- Onshore flow continues shower potential until a stronger front arrives Tuesday.

LONG TERM

Relatively warm, wet, and windy will continue to be the trend through the middle of the upcoming week across SE AK. Showers will diminish into Tuesday from a short wave to start the week. A low moving into the Bering Sea in the early week will push an elongated front across the Gulf, with an embedded low expected to form in the vicinity of Kodiak Island Tuesday. By Tuesday evening, this gale force front should have pushed into the central gulf and continue to approach the panhandle, likely pushing inland sometime Tuesday night into Wednesday morning.

A surface ridge pushing up from the south into the panhandle will be pinched, and lead to a tightening N/S gradient across the region for this timeframe. A High Wind Watch has been issued for Skagway for Tuesday night for potential wind gusts up to 60 mph. For a majority of the N/S oriented channels, gale force winds will develop ahead of and along the front as it approaches, with storm force gusts likely along Lynn Canal late Tuesday through early Wednesday morning.

With the front being fairly progressive from west to east, associated moderate to heavy rainfall is not expected to result in any flooding at this time. Persistent southerly flow ahead of and along the front will result in rising snow levels up to around 2500 ft in the southern panhandle ranging to around 1000 ft in the northern panhandle. Higher elevations could see some wet snow accumulation, however little to no snow accumulation is expected for communities at sea level from this first system.

On the heels of this strong front, another low is expected to move into the gulf from the south, and model guidance continues to waver not only on the track of this system, but the intensity as well. A more southerly track could cause a northerly wind shift in the inner channels and allow for colder and drier air to filter in, increasing chances for some mixing or even minor snow accumulation at sea level for the northern inner channels, particularly Haines and Skagway. However if the low tracks too far south, then moisture may not make its way that far north. On the other hand, if the track is farther north, strong winds will likely spread over a larger part of the outer coast and inner channels, but the dominant precipitation type would likely be rain across the area due to stronger southerly flow at the surface as well as aloft, steering the system.

Looking ahead to the end of the upcoming week, there is some potential for high pressure to build over the interior and slide into the Yukon territory and British Columbia which could yield sustained offshore flow and a return to drier and colder conditions across the panhandle.

AVIATION.../through Monday afternoon/

Generally MVFR flight conditions today as one shortwave leaves the northern panhandle and another pushes into the southern panhandle. Periods of IFR VIS/CIGs are possible for PAHN and especially PAYA under steadier rain. Additionally, fog and low stratus could lead to IFR VIS/CIGs tonight for the northern/central TAF sites, especially PAJN, PAGS and PAPG. Further south, another shortwave lifting north into the panhandle will bring more rain and MVFR VIS/CIGs later this afternoon/evening into Monday. The rain will slowly work north overnight and reach central panhandle by Monday morning and the northern panhandle by the afternoon, with MVFR flight conditions likely.

Gusty winds in the north are diminishing from their maxima overnight, but will likely remain somewhat gusty through the afternoon, especially at Skagway where winds could last into tonight before diminishing. Otherwise, winds at ground level in most areas are 10 kt or less for the most part with some occasional higher gusts in heavier rain bands. These winds will likely gradually diminish into tonight. Pockets of LLWS will diminish today for PAJN. LLWS will increase tonight into Monday for the southern panhandle with winds 2kt aloft 25-35kt.

MARINE

Outside (Gulf and Coastal Waters): Multiple shortwaves moving through the panhandle will keep active weather in the forecast for the week. Showers linger off the southeastern gulf coast, reinforced by a weakening shortwave moving into the southern panhandle through Sunday afternoon. Breaks in the clouds are probable as shortwaves and showers continue to move into the panhandle. Wave heights between 8 to 12 ft with the highest waves in the southern Gulf continuing through Sunday night before diminishing to 6 to 8 ft Monday. Moderate to fresh breezes with periods of stronger gusts persist in the gulf waters through the early week before a strong system moves into the northeastern gulf Tuesday afternoon.

Inside (Inner Channels): Continuous shortwaves are bringing light rain with fresh to strong breezes through the panhandle early this week, with periods of breaks in the clouds following behind. Through Sunday night, winds will continue diminishing to moderate breezes for most of the inner channels, barring Northern Lynn Canal and Clarence Strait. While Clarence Strait will continue seeing fresh breezes with isolated strong to near gale force gusts through Monday, Northern Lynn Canal will attempt to hold onto fresh to strong southerly sustained breezes with gale force gusts through the daytime hours of both Sunday and Monday. Shortwaves and showers will continue to move through the panhandle into Tuesday, which may allow for periods of heavier rains and sporadic gusty conditions. A strong system approaching in the northern gulf is forecast to reach the outer coast of the panhandle Tuesday night, which is currently looking to bring gale force sustained winds with storm force gusts to a majority of the inner channels. Northern Lynn Canal looks to see the strongest of these winds, so a high wind warning has been issued for the Skagway Borough.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Wind Advisory until 9 PM AKST this evening for AKZ318. High Wind Watch from Tuesday evening through late Tuesday night for AKZ318. MARINE...Small Craft Advisory for PKZ012-022-036-641>644-651-652-661>664- 671-672.