textproduct: Juneau

SYNOPSIS

Key Messages:

- A low pressure system over the southern gulf will bring more rain to the central and southern panhandle into Friday, with the heaviest amounts south of Sumner Strait. - Expect increased marine winds, mainly over the southern gulf and Clarence Strait, today into Friday.

- A ridge builds over the gulf later Friday into Saturday allowing for winds to weaken and precipitation chances to gradually decrease.

LONG TERM.../Saturday through Wednesday/

At the start of the long term period a low will be situated over the southeastern Gulf of Alaska. The associated frontal system will extend over the southern portions of the panhandle and will bring light rain showers along the Coastal Range as well as for communities Petersburg south. While the low will is expected to remain mostly stationary the strength of which will weaken through the weekend which will result decreasing rain chances through the weekend. For the northern panhandle easterly flow will dominate, and while chances of precipitation is lower compared to areas to the south, it is non zero. That said, precipitation for the northern areas is expected to be more showery in nature. Due to the low weakening the chance of thunderstorms that were mentioned in the previous forecast discussion seem to becoming less likely. That said, the thunderstorm chances will have to be monitored closely as it will be very dependent on the exact track and strength of the low.

Looking towards the start of the next week, models are in agreement that a ridge will move into the Eastern Gulf. The exact amplitude and placement of the ridge axis is still a little bit uncertain, however it will dictate where the generalized onshore flow and wetter conditions will be placed. The current line of thinking is that these conditions will be Icy Bay westward on Monday and will move east through through mid week.

AVIATION.../Through 12z Friday/

The panhandle is split between two regimes Thursday, with areas south of Frederick Sound expected to feel the influence of a lingering front moving through the southern panhandle this afternoon. The northern half of the panhandle has been seeing clearing skies with light winds through the morning. A few areas of patchy fog have developed overnight, but for the most part have remained thin and away from the runway. Skies are expected to continue to be relatively clear through the day, with any lingering clouds remaining high and broken. 10 to 15 kt sea breezes will increase through midday. A layer of high clouds is currently moving northward over the southern panhandle this morning, preceding a lower layer around 2500 to 5000 ft which is expected to move inland through midday today. Conditions are expected to remain VFR through the central panhandle with this front, though the southernmost areas of the panhandle may dip down to MVFR periodically with heavier rainfall. Southeasterly wind gusts are expected to increase for these southernmost areas as well, with LLWS, mainly speed shear, possible for PAKW through the afternoon.

MARINE

Outer Waters: The gulf waters are dominated by two regimes today, with light northwesterly breezes in the northern gulf and a front bringing strong breezes to near gale force southeasterly winds through Dixon Entrance and into the southern gulf. 8 to 12 ft wave heights are expected in the southeastern gulf off the western coast of Prince of Wales and Southern Baranof Islands through Thursday. As the front dissipates overnight, winds and waves will subside and remain benign through Friday before ridging sets up over the gulf Saturday.

Inside waters: Patchy fog developed overnight through sheltered inlets and channels, and will dissipate through the morning. Northerly winds will continue through the morning as a front moves into the southern panhandle. This front will bring moderate to fresh southeasterly breezes through Clarence and Sumner Strait, lingering in Clarence through Friday morning. The rest of the channels will stay relatively benign through the period, with 10 to 15 kt sea breezes expected to develop and shift winds onshore through some of the northern channels midday. Winds that turn onshore will turn back offshore overnight. After the front dissipates through Friday morning, any lingering winds will diminish through the day.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Small Craft Advisory for PKZ641-642-661>663.