textproduct: Juneau

UPDATE

Updated the Aviation Section for the 18z tafs. Additionally, increased winds for Cross Sound, Icy Strait, and areas directly west offshore for the rising pressure and isallobaric wind in the area. Mariners may see wave heights much higher than expected for waters in Icy Strait, particularly near the mouth of Glacier Bay. This is due to stronger southwesterly swell colliding with easterly winds currently occurring.

SYNOPSIS

Key Messages:

- A cold front will bring rain and gusty winds to the panhandle on Monday, along with much cooler temperatures.

- The cooler, more seasonable conditions will prevail this week with mostly cloudy skies and occasional showers as multiple systems pass through the region

LONG TERM

Extremely little changes to the overall long term forecast, with the only large scale feature of note being a surge of energy from the eastern Bering Sea possibly moving into the northern Alaska Gulf by this weekend. Details are still low on this possible event, but worse case scenario from current solutions is another round of moderate to possibly heavy rain for primarily the northern half of the panhandle, along with an increase in winds. Otherwise, mid to late work week has multiple waves move through mainly the northern half of the panhandle. These waves do not look to bring rain totals greater than an inch, with rain rates not exceeding light intensity.

AVIATION

Dreary flying conditions this morning, as a front moves through the panhandle today, with widespread IFR to pockets of LIFR due to both CIGs and VIS. A pocket of heavier rain, currently around the Sitka area, is moving southeast toward the southern panhandle during the afternoon timeframe. Moderate to heavy rain, ceilings generally AoB 900 ft, and visibilities less than 2 miles are associated with this pocket. As the front passes, general onshore flow with mostly MVFR CIGs and the occasional rain showers, mainly on west to southwest facing mountains, will persist overnight. Worse conditions, around low MVFR, are expected largely along the coast, with CIGs AoA 2000 ft for the inner channels.

While winds at the surface are elevated, particularly near Haines and Skagway with gusts up to 40 knots, the LLWS concerns have largely ended, as the front has weakened to below category. Winds for most areas are expected to slack overnight, with a chance of some fog development possible for the central panhandle. Confidence is low for any fog development at this time.

MARINE

Outside: As of this discussion, winds near Cape St. Elias and buoy 82 have begun to decline behind the front advancing north and east across the gulf. As of 5am Monday, seas of 10 ft with a period of around 8 seconds were still being reported. Further east at the Fairweather Grounds, buoy 83 was still reporting seas closer to 5 ft with a period around 16 seconds. From Cross Sound south to Prince of Wales, fresh to moderate breezes are still expected through the day before a westerly wind shift behind the front through the afternoon and evening hours. For the northern coast, large and confused seas from building southwest swell mixing with southeasterly wind driven seas will gradually subside through the evening hours behind the front. As you move from Cross Sound to Prince of Wales, expect southwest swell to be a bit more prominent, with southerly wind chop riding on top. Significant heights of 8 ft near Cape Edgecumbe, and 6 to 7 ft west of Prince of Wales.

Inside: Current forecast shows confidence for building moderate breezes across Chatham and Stephens Monday, with strong breezes impacting Lynn Canal. As of 5am Monday , northern Lynn Canal is maintaining sustained southerly winds around 25 kt and this is expected to continue and strengthen slightly through the afternoon hours as the front lifts inland. Folks in Glacier Bay will feel southeasterly winds of moderate to fresh breezes, becoming southerly as the front moves over the area Monday afternoon. Caution advised for Reid Inlet and other bays/inlets sheltered from southeast winds but exposed to southerly blows in Glacier Bay.

While some guidance highlights the possibility of moderate to fresh breezes in Clarence Strait today, current thinking is the front and resulting pressure gradient will remain strongest in the central and northern Panhandle. As a result, sustained winds are expected to remain below fresh breezes for the south. Forecasted peak winds show up to 15 knots in Clarence for Monday afternoon.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Wind Advisory until 10 PM AKDT this evening for AKZ318. MARINE...Small Craft Advisory for PKZ012-022-053-641>644-651-652-661>664- 671-672.