textproduct: Juneau

UPDATE

Updated Aviation discussion for the 18z TAF issuance

LONG TERM

The long term weather for the end of the week continues to look fairly quiet with high pressure remaining over the panhandle before a weak low pressure moves into the northern Gulf. Until then, weak outflow winds will continue with the gradient along the Coast Mountains. With the weak outflow, surface temperatures will continue to be cool while places that see increasing winds will see temperatures jump as temperatures aloft are warmer than at the surface.

For the end of the week and into the weekend, ensemble guidance wants to bring a weak surface low into the northern Gulf that will bring a return to seeing some precipitation in the area. With the weak, shallow inversions, any mixing would result in most places seeing rain while the far northern panhandle could see snow at higher elevations.

CPC guidance suggests overall warming temperatures next week with the more active weather, but due to the weakening outflow winds persisting in Lynn Canal, northern panhandle communities still have a chance to see this precipitation fall as snow before most likely changing over to rain by early next week. Precipitation still looks to remain on the lighter side of what is typical for Southeast Alaska, though continued onshore flow and another potential broad low following behind should keep relatively consistent precipitation in the forecast for next week.

AVIATION.../thru 18z Saturday/

Largely VFR conditions across the panhandle as breezy offshore continues to pour out of interior passes and down Lynn Canal Friday morning. While no significant LLWS is present or forecast, approaches to Haines and Skagway would likely include a few bumps on the way down. Dense fog and a marine layer continue to be the only other significant aviation hazard this morning, limited now to the northern gulf coast from Kayak Island eastward towards Yakutat. As of this discussion, the marine layer has lowered to the surface and dropped VIS to 1/4 SM or less there. These conditions are expected to persist through the morning hours, with a chance for minor improvement this afternoon before returning later tonight.

MARINE

Outer Coastal Waters: Dense fog remains over the northern gulf through the first half of the day on Friday, before slowly being pushed off to the west. Otherwise, winds remain 10-15 kt, with stronger winds generally remaining for the more open waters of the Gulf, and lighter winds closer to the coast, especially after coastal outflow areas subside through the day on Friday. This pattern will last through the weekend, before a system enters the Gulf late Sunday, bringing an upward trend for winds and seas.

Inner channels: Strong breeze (22 to 27 kt) winds in Lynn Canal and near typical outflow areas will slowly subside through Friday. In their wake, 5 to 10 kt winds predominate across the inner channels as the pressure gradient slackens, with the lighter winds remaining through the weekend, before a system arriving late Sunday or Monday brings with it a return to elevated winds and seas associated with a more active weather pattern.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Freezing Fog Advisory until noon AKST today for AKZ317. Wind Advisory until 6 PM AKST this evening for AKZ318. Freezing Fog Advisory until 9 AM AKST this morning for AKZ328. MARINE...Small Craft Advisory for PKZ012.