textproduct: Juneau

UPDATE.../to add the 18z aviation discussion/

SYNOPSIS

Key Messages:

- Continue cool with isolated to scattered showers across the northern panhandle today.

- Drier with clearing possible for the southern half of the panhandle, with daytime highs possibly exceeding 65 degrees.

- A weather front is expected to move into the panhandle on Friday, bringing rain to areas from Icy Strait corridor on south.

LONG TERM

Looking toward the Fourth of July, residual onshore westerly winds look to keep rain chances elevated for much of the panhandle except Haines and Skagway. Overall, low level flow looks rather weak, therefore, the threat shifts towards a low ceiling and aviation risk moreso than anything else. Expect to see these impacts primarily on west facing slopes.

Going into the weekend and next week, a relatively intriguing deep upper level moves near the panhandle. While confidence in the track of the upper level low along with the placement of the jet streak is moderate to low, there is enough confidence in today's guidance to say that we may see an unseasonably strong front move in from the south. With the strength of the upper level low, the divergence aloft, the jet possibly exceeding 50 knots at 500 mb, and a possible dry slot behind the initial band during the daytime, these types of setups could have convective storms associated with stronger wind gusts. Ultimately, details are sparse and confidence is low, but this situation will be actively monitored over the coming days.

AVIATION.../Until 18Z Friday/

The weak low is continuing to push into northern British Columbia, today, keeping light rain showers & MVFR CIGs over the Icy Strait Corridor from PASI to PAHN into this afternoon. By late this afternoon, that area will improve to VFR as the low pushes further into BC & away from our area while further weakening. For the southern Panhandle, expect VFR flight conditions until a frontal system approaches & begins to push into that area late tonight, which is when primarily their CIGs will start lower to within the MVFR flight category. SFC winds remain benign for most areas. PAGY continues to be the exception with the combination of the pressure gradient over that area & the sea breeze causing rather gusty winds during the day. LLWS values are not a concern through the TAF period.

MARINE

Outside (Gulf and Coastal Waters): Winds across the Gulf of Alaska are below 10 kts with on shore flow and an upper-level disturbance over the Northern Alaska Panhandle. Conditions are expected to be fairly benign during the day Thursday, but a low pressure system and front are expected to bring 20 kt winds and seas up to 6 feet Friday. Some wind gusts could approach 30 kts in the Gulf Friday, but the low is expected to move southeast Saturday and weaken. By Sunday, a stronger low pressure system looks to approach the area. For more information on the system expected to arrive Sunday, please read the long term discussion.

Inside (Inner Channels): Due to an upper-level disturbance, the strongest winds this morning are in Northern Lynn Canal. By Thursday evening, winds are expected to diminish, but a front early Friday could bring 10-15 kt winds into the inner channels. Right now, the strongest winds look to be in Stephens Passage, Fredrick Sound, and Clarence Strait. The low pressure will move to the southeast Saturday, so winds and waves will diminish.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Small Craft Advisory for PKZ012.