textproduct: Juneau

SYNOPSIS

Key Messages:

- Showers capable of producing lightning have been observed moving onshore over parts of the southern and central panhandle overnight and are expected to continue through Wednesday.

- Active weather will continue through Wednesday night with low pressures moving into the Gulf bringing active weather to the area.

- Cooler but seasonable temperatures for the period, with daytime highs generally in the 50s.

- Potential for a break in the weather Thursday into Friday as high pressure moves in temporarily ahead of the next system to affect the panhandle.

LONG TERM..../Friday through Monday/

As the low dissipates over the southern Gulf and shifts east, high pressure builds over SEAK, bringing dry and mild conditions, lighter outflow winds and mostly sunny skies for Friday. The only exception could be along the central and northeast Gulf coast as a weak boundary lifts creeps northeast. High temps will be in the mid to upper 50s, with a few low 60s possible for POW Island. A pleasant end to the week before the next fronts impact the region this weekend. The big player that will send the fronts into the Gulf and through SEAK will be the remnants of Typhoon Dujuan and associated upper-level low/trough that will slowly swing through southern interior into the Gulf through the weekend. Multiple fronts/lows will pivot around the southern periphery of the upper trough through the Gulf and into the panhandle over the weekend. The initial front will lift northeast through the Gulf into the panhandle late Friday night into Saturday, with another quickly on its heals pushing east through the Gulf into the panhandle on Sunday. Multiple rounds of moderate to heavy rain and gusty winds are expected with each frontal passage, especially with the Sunday system it will tap into deeper feed of moisture out ahead of it. Additionally, a few thunderstorms will be possible with cooler temps aloft with the upper trough approaching resulting in some modest instability. For early next week, model guidance begins to diverge quite a bit, but the general trend is for the active pattern to continue with the upper trough/low persisting near to west of the area, with another front/low lifting northeast somewhere into the Gulf and into the panhandle, bringing another round of gusty winds and moderate to heavy rain. Some guidance is quite aggressive with this low and bringing gales into the Gulf, but confidence on location and timing of this system is quite low given the model spread.

AVIATION.../Through 12Z Thursday/

Scattered showers will continue pushing northeast across the region this morning. Some may be locally heavy, but most of the heaviest activity is likely to remain over the coastal waters. Like yesterday, a few thunderstorms are again expected through the day. Overall, precipitation coverage and intensity will gradually decrease this evening, and there could be some breaks in cloud cover overnight. Winds will remain gusty at times through this evening, up to about 25kt, before decreasing tonight.

MARINE

Outer waters: Hazardous marine conditions will peak on Wednesday, driven by a broad band low lifting through the gulf that will maintain steady southeast to southerly winds of 30-35kts, widespread Small Craft Advisory conditions, and steep, heavy ocean swells of 8-14ft. A slight chance of thunderstorms is possible along the southern outer coast through the day Wednesday, which may bring sudden wind shifts and drops in visibility during heavy downpours. High winds will likely drop off dramatically on Thursday as the pressure gradient relaxes, with breezes shifting easterly at 10-15kts, though heavy ocean swells will be slow to decay and likely to remain elevated through the first half of the day Thursday before gradually settling. A brief break in hazardous conditions will come to an end on Friday as a new frontal system lifts into the gulf.

Inner channels: Winds across the inner channels have underperformed the initial forecast, prompting a significant downward adjustment to speeds and an earlier ramp-down that originally forecasted. Most of the north/south oriented channels have not reached the speeds expected due to the mainly east/west orientation of the pressure gradient and lack of channeling of the winds. The pressure gradient has supported windier conditions overnight in Stephens Passage and Fredrick Sound in particular, which are expected to see winds up to 25kts through the morning. Around 10am on Wednesday, the pressure gradient is expected to slacken across the inner channels, leading to an overall reduction in winds speeds by late Wednesday. Thursday, and especially Friday, could see some light localized sea breeze effects with clearer skies expected.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Gale Warning for PKZ664-671. Small Craft Advisory for PKZ022-031-034-641>644-651-652-661>663- 672.