textproduct: Juneau

UPDATE

Update to include the 18Z TAF issuance. The forecast remains largely on track this morning. Winds have remained light with clear skies over a large majority of the panhandle. Some areas of patchy fog have developed, but it is very thin and occurring only over very isolated areas. The next larger system arrives late tonight into Sunday.

SYNOPSIS

Key Messages:

- Relatively benign winds and partly cloudy skies continue until a gale force system arrives overnight Saturday into Sunday.

- Widespread precipitation and strong winds Sunday, with potential for accumulating snowfall in the northern panhandle. A winter storm watch has been issued for the Klondike Highway.

- Another system arrives Tuesday night.

LONG TERM.../Monday through Wednesday/

Onshore flow largely continues through Monday night as another wave of precipitation moves through closely behind the remnants of the frontal system from Sunday, before chances begin to diminish across the panhandle Monday night into Tuesday morning. The warming across the panhandle following the Sunday system will keep the area transitioned to rain by Monday, with the exceptions of the highways. The heaviest rain from Sunday will have passed, with much lower QPF amounts expected into Monday, diminishing into Monday morning. The only area that is expected to see snow is along the highways, with more of a mix on the Haines Highway and wet, dense snow along the Klondike Highway Monday, with accumulation of less than an inch Monday. Tuesday continues to show confidence on a low level ridge forming over the panhandle, as well as 500 mb ridging rebuilding over the Gulf again after the prior upper level shortwave moved through by Monday, allowing for a brief lull on Tuesday. This however will mainly be for the southern half of the panhandle, as the position of the ridge will allow for some onshore flow to remain moving into the NE Gulf coast and keeping PoPs higher Icy Strait corridor northward and some light precipitation over the area. The southern panhandle will still see some cloud cover even with the ridging setting up, though precipitation chances will decrease to 20 to 40% Monday night through midday Tuesday.

The next front moving through will begin to impact the NE Gulf Coast and Yakutat areas into Tuesday night, before moving eastward across the panhandle. This front will move across the panhandle through Wednesday, bringing another round of rain and continued warmer temperatures to the panhandle. Highs for the northern half of the panhandle will be in the mid to high 40s, while the southern panhandle will see temperatures around 50 degrees, bringing us close to some record temperatures for this time of year if these warmer temperatures pan out. In terms of precipitation, the majority of the panhandle will see 850 mb temperatures warming to around 0 degrees C, and snow levels between 3000 and 5000 ft alongside the warmer temperatures and wet bulbs at the surface, bringing light to moderate rain across the area and snow mixing in only at higher elevations. The only area not expecting rain will be the Klondike Highway, with snow levels remaining just around 3000 ft allowing for wetter snow to continue, but with little to no accumulation expected. Overall the NE Gulf coastline will see between 1 and 2 inches of rain in 24 hours from this system Tuesday night into Wednesday, and generally less than 1 inch in 24 hours for the rest of the panhandle.

AVIATION

Widespread VFR conditions continue across the panhandle with clear skies over most of the area. Along with scattered to clear skies, low winds will persist well into tonight before the next front starts to make its way over the panhandle. This front will first impact coastal areas starting late tonight into Sunday morning. This system will bring lowered ceilings and visibilities into MVFR flying conditions, with times of IFR possible, as moderate to heavy precipitation spreads across the panhandle. Precipitation will mainly be rain, with areas of snow or wintry mix from the Icy Strait Corridor northward Sunday morning. Winds will also increase with LLWS around 2000 ft returning. LLWS will first return near the northeast coast before spreading inland affecting almost all of the panhandle.

MARINE

Outside: Southeasterly winds in the central gulf have decreased to 10 to 15 kts overnight, seeing only a brief break before the next system moves into the eastern gulf through Saturday. A large swath of 25 to 30 kt winds moving towards the northeastern outer coast of the gulf through Saturday evening will continue to intensify overnight. By Sunday morning, strong southeasterly gale force winds (41 to 47 kts) with potential for storm force gusts (48 to 55 kts) will be pushing inland the coast from Cape Ommaney to Cape Suckling. Strongest winds from Cape Spencer to Cape Suckling are expected to peak through midday Sunday. Gulf winds largely decrease to fresh to strong breezes (17 to 27 kts) overnight with southwesterly onshore flow continuing through Monday. Another system is set to move into the eastern gulf Tuesday.

Wave heights have decreased to around 5 to 7 ft through Sunday morning, and are expected to steadily increase through Saturday afternoon to eventually return to 10 to 15 ft at a period of 10 seconds by Sunday morning. Heights will increase to 15 to 22 ft along the northeastern gulf coast where winds are strongest midday Sunday. The gulf will return to a more uniform 10 to 15 ft with a longer period of 15 to 18 seconds by Sunday night. South to southwesterly 5 ft swell will be overtaken by 10 to 15 ft of southerly swell following the front Sunday morning before turning southwesterly and decreasing to 8 to 10 ft.

Inside: Very weak outflow winds around 5 kts through the inner channels will remain light through Saturday before the gale force front moves into the eastern gulf overnight into Sunday. Winds ahead of the front will turn onshore and proceed to largely increase to strong breezes to near gales (22 to 33 kts) early Sunday morning. Icy Strait winds will remain easterly through Sunday. As the front continues to push onshore through the day, gale force gusts (34 to 40 kts) will increase through the channels. Wave heights around 1 to 2 ft will increase to around 4 to 6 ft following the stronger winds, with channel entrances seeing up to 10 ft through Sunday night. Winds and waves will steadily decrease through Monday before another system moves into the eastern gulf Tuesday.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Winter Storm Watch from Sunday morning through late Sunday night for AKZ318. MARINE...Small Craft Advisory for PKZ642>644-651-652-662>664-671-672.