textproduct: Juneau

SYNOPSIS

Key Messages:

- A front is moving over the panhandle, bringing primarily rain showers first, before mixing in snow overnight.

- Tuesday is expected to see a clearing from north to south, with increased chances of sun.

LONG TERM

The low complex that is dominating the weather pattern in the short term is expected to move SE and be over the southern panhandle by mid week. By late Tuesday/early Wednesday the low will begin to weaken and continue drifting south. As this occurs the northern half of the panhandle as well as the northeast Gulf Coast will get a break from precipitation starting later Tuesday. The southern portions of the area are expected to remain in a showery regime until later Wednesday. With overnight temperatures being in the mid to upper 20s precipitation during the overnight/morning hours could be a rain/snow mix with snow accumulations being minimal if at all.

As this low moves out of the area a ridge of high pressure is expected to move over the Gulf of Alaska. Models are well aligned with the amplitude and placement of the ridge remaining over the southern portion of the gulf during the later half of the week. This will result in a weak trough setting up along the North and Eastern Gulf Coast, yielding showery conditions for the area. None of the showers are expected to be particularly impactful.

AVIATION

A low-pressure system dwells in the western Gulf of Alaska tonight, bringing precipitation to the coast and northern sites first. Showers will start light and intermittent, becoming most consistent and widespread across the panhandle by 6Z. Yakutat will see precipitation taper off around 12Z as the low tracks south, though MVFR conditions will persist. Expect MVFR ceilings (1500-3000ft), with sporadic VFR pockets. Fog is not expected at most sites due to decent mixing, but Yakutat may see radiational fog supported by calm winds and clear upper levels.

Northern sites have a low chance of a rain/snow mix in the evening/early morning due to cooling and increasing saturation aloft, but persistent warm, southerly winds make surface impact unlikely. Visibility will remain good, and wind shear is not a concern with tonight's front. Precipitation will lighten tomorrow as the system moves onshore and breaks up. Gusty northern winds will weaken overnight, and a general decrease in wind speeds is expected across the panhandle tomorrow.

In the southern panhandle, the sunny day is quickly turning into rain as the evening hours grow closer. Light rain and showers will bring lower ceiling into the area, handing between 2,000 and 3,000 ft, except for Sitka, which can expect ceilings to hang around 1,500 ft until late tonight. All locations in the Southern Panhandle are expected to stay MVFR due to ceilings, with visibilities staying around 6SM. Conditions look to improve to VFR as the night progresses with possibilities of ceilings dipping back to down to MVFR levels. Locations will see rain through tomorrow.

MARINE

Outside Waters:

A low in the northern gulf is generating fresh to strong westerly to southwesterly breezes for the eastern gulf through tonight. Expecting to see this low shift south and weaken through Monday night. Long, wide fetches with consistent westerly winds look to build seas from 5 ft up to 10-13 ft at 9 to 10 seconds before diminishing slowing Monday night.

Inside Waters:

Looking to see a gradual increase in winds, as a front associated with the northern gulf low continues to work its way over the panhandle. Similar to the outside waters, expecting to see fresh to strong south to southwesterly breezes for Frederick Sound, Sumner Strait, Southern Chatham Strait, and SW-NE channels in Clarence such as Behm Canal. As the low shifts southward, expecting to see a transition of winds from south/southwesterly to more southeasterly. Largest uncertainty is when Lynn Canal will diminish from the 20 knots it is currently experiencing. Current forecast has around 9 AM Monday morning, but this could be as late as 3 PM.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Small Craft Advisory for PKZ022-031-641>644-651-661>664-671-672.