textproduct: Juneau

SYNOPSIS

Key Messages:

- Quiet weather continues for the first half of the weekend before cooler weather returns for the second half of the weekend.

- A pattern change looks to arrive Monday as rain chances return from north to south. Chances for wetting rains increase significantly for next week.

LONG TERM

A couple of interesting features for Southeast Alaska for the next work week as the ridge plaguing the area finally breaks down fully on Monday. An upper level low moving up from the Aleutian Chain looks to swing across a negatively tilted shortwave across the northern gulf. The warm sector and warm front associated with this trough looks to move into the northern half of the panhandle first, raising snow levels briefly to well over 10000 ft and inviting warm rain processes. This combined with orographic lifting will result in the heaviest portion of rainfall, with Yakutat having a 80% likelihood of exceeding 1.5 inches of rain overnight on Monday. As the warm front weakens and becomes occluded, rainfall drops rather dramatically to less than a half inch during the latter portion of Monday. Winds are expected to roughly follow the same story, with a barrier jet forming along the NE gulf coast, with up to gale force winds between Icy Cape and Cape Suckling, and strong southeasterlies elsewhere.

As the southwesterly energy surges over the Coast mountains, expecting to see some leeside troughing which, in combination with the continued ridge axis in the southern panhandle, will cause a significant southerly pressure gradient. Its during this time (Monday) that moderate to strong southerly breezes for Chatham Strait, Stephens Passage, and Lynn Canal will begin, with Skagway possibly exceeding 40 mph gusts.

Beyond Monday, the active pattern continues, but confidence on individual features drop from moderately high to moderately low. Even still, confidence is increasing that another system may be in the works for Wednesday, bringing more rain and wind.

AVIATION

VFR conditions prevail across most of the panhandle this morning. The exceptions are along the outer coast and into Cross Sound where marine layer low clouds (and some fog) has moved in overnight creating areas of IFR or lower conditions. Those marine layer clouds are expected to remain mostly along or just offshore of the outer coast today before starting an inland push tonight. Clouds with MVFR or IFR ceilings will likely reach up Icy Strait to Gustavus or Hoonah, up Peril Strait, and into Craig and Klawock by late tonight. May also have some clouds reaching up southern Clarence Strait into Ketchikan and Metlakatla as well. Other then that the only other concerns are afternoon sea breezes that may be up to 15 kt in some locations.

MARINE

Inside water...Still a mostly quiet marine forecast for the next few days. Mostly lighter winds with afternoon sea breezes being the main driver of any higher winds. Marine layer low clouds and fog will likely be encountered near ocean entrances and Cross Sound today which may extend into Icy Strait, Peril Strait, and southern Clarence late Sat night and Sunday morning. Change starts to come for Monday as a new front moves in from the west bringing some breezy conditions (up to 15 to 25 kt) and precipitation for the northern inner channels and Yakutat Bay.

Gulf Waters: One more quiet day for the gulf before a new front begins to move in on Sunday and Sunday night. Winds are currently mostly NW at 15 kt or less with 5 ft or less seas. Some areas of low clouds and fog are present along the outer coast this morning bringing some reduced visibilities to some areas and will likely persist into Sunday. The new front will bring SE winds to 20 to 30 kt mainly for the northern and central gulf Sunday night before winds switch to westerly post front and diminish to 10 to 20 kt on Monday. Sea likewise will be building Sunday night into Monday up to around 9 ft before slowly starting to subside there after. This will be first accomplished by winds building wind wave Sunday night followed by a 5 to 6 ft SW swell moving into the area on Monday.

FIRE WEATHER

HYDROLOGY

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Heat Advisory from 10 AM this morning to 7 PM AKDT this evening for AKZ319-328. MARINE...Small Craft Advisory for PKZ651-652-663-664-671-672.