textproduct: Juneau

SYNOPSIS

Key Messages: - Northerly winds build across the inner channels Thursday night, strongest marine winds expected in Lynn Canal. - High pressure returns through the end of the week with drier conditions, more sunshine, and high temperatures in the mid 60s to low 70s.

LONG TERM.../Saturday through Tuesday/

Still no major changes are expected in the long term forecast, as a high pressure ridge dominates the Gulf for the foreseeable future, bringing consistently dry and benign weather. Beginning Saturday morning, winds across the inner channels and coastal waters are expected to weaken and remain at or below 10 knots. Afternoon sea breezes will likely develop with daytime heating, but are not expected to cause significant impacts.

The greatest uncertainty in the long term is whether a weak disturbance will bypass the northern panhandle early next week. Model guidance generally agrees that high pressure will strengthen and block most appreciable precipitation, however, there is a small but increasing chance of light rain reaching the northern panhandle/outer coast region by midweek. Highest confidence is that most precipitation will stay over the mainland interior, though could still see widespread cloud cover move in from the north by Monday. Overall, generally dry conditions with daytime temperatures rising into the mid 60s to low 70s across most of the region, continuing to remain seasonably warm through midweek.

AVIATION

Though fog hung around near PAPG for most of the afternoon, all TAF sites are running at VFR with clear skies or cigs AoA 10-kft in the northern panhandle, and cigs between 3 and 6 kft in the southern panhandle. Expect a bit more clearing and lifting to go on during the overnight. Wind forecast for northern Lynn Canal (PAHN/PAGY) is a touch lighter than previously forecast, but gusts of 15-20 kt are still possible this evening/tonight.

Widespread fog is unlikely, but given how long PAPG/PAWG stayed under, they are suspect for some more fog to drop vsby Friday morning to low end MVFR levels. By the afternoon, everything should be back into VFR territory.

MARINE

Outer waters: No changes from the previous forecast, with the persistent message of northerly to northwesterly winds. High pressure continues to build in the Yukon, with Whitehorse around 1025 and rising. A shortwave trough extending down from northern British Columbia looks to drive the stronger pressure gradients exiting southern Chatham Strait and out of interior passes along the Fairweather Range. Not expecting these winds to exceed 20 knot sustained, with little gust factor. These winds are expected to prolong any wave heights in small craft criteria, 8 ft, through Friday morning. Otherwise, beyond Friday morning, expecting these northwesterlies to continue into the mid weekend at around 10 knots.

Inside Waters: Slight deviation from the previous forecast, primarily in the Taiya Inlet area. While Lynn Canal is increasing nicely, around 20 knots at time of writing, Skagway and Taiya Inlet are largely calm. This is due to the high pressure in the Yukon not extending as eastward as previously anticipated, dragging the pressure gradient vector more cross channel. As this means the pressure differences along the channel are relatively lax, not much wind has resulted. Still expecting these winds to increase, but not until late tonight/early Friday morning. By this point, the trough will be exiting, and daytime heating and thermal troughing looks to take over, ruining any progress of stronger winds in Taiya Inlet by midday Friday. Otherwise, the message is largely unchanged, with small crafts down N/S facing channels for 25 knot winds, diminishing Friday morning. Saturday conditions look increasingly lax, with little influence from synoptic scale features, and local effects dominating.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Frost Advisory from 1 AM to 9 AM AKDT Friday for AKZ317-320-321- 325. MARINE...Small Craft Advisory for PKZ011>013-031>033-641>643-661>663.