textproduct: Juneau

SYNOPSIS

Key Messages:

- A Winter Storm Warning remains in place for Yakutat into Thursday Evening.

- Colder temperatures are in store for the end of the week into the start of next week.

- Offshore flow with break in snowfall begins today and lasts through the early weekend.

LONG TERM

Cold, stable, and predominantly dry weather pattern is currently expected through Saturday night with higher confidence. The arctic air mass situated over the Yukon, further amplified by a strong upper-level ridge will dictate much of the weather going into the weekend. The northern channels, including Haines and Klondike Highway will experience the coldest conditions, with daytime highs likely remaining in the single digits, and overnight temperatures dipping below zero near White Pass and Haines Customs. The low pressure currently lingering near the NE gulf coast finally looks to dip south on Friday, bringing changes of snow showers for the outer coast mainly. Not expecting these snow showers to move into the inner channels as much, due to dry and cold air filtering in from the north.

This pattern begins to shift on Sunday as upper level forcing drives a low pressure system towards the northern coast. The main source of uncertainty for this incoming system is the interaction with the high pressure in the Yukon. The EPS is definitely the most aggressive in breaking down this high pressure, with the GEFS and GEPS keeping the high pressure from breaking down as much in the means. One interesting point is the currently non operational HGEFS show an in between solution in the means, which would still keep most of the panhandle cold enough for snow. While not included in the current analysis, it more points to the unknowns for how this energy will interact with the cold, dry air in Canada. While there is high uncertainty in this part of the forecast, what can be said is moisture is highly likely (>80%) to stream back into the panhandle bringing more precipitation. The main question going forward is where will get the most precipitation, and what weather type (rain, snow, exc) could fall at each location.

AVIATION.../Until 12Z Friday/

The northeast gulf coast area, including PAYA, will experience periodic bands of snow showers through this evening, which will generally reduce conditions into the MVFR/IFR category range, possibly temporarily reducing visibilities down to the LIFR category under heavier snow showers. For the remainder of the northern Panhandle, conditions will be in the VFR/MVFR category range with improving conditions as we progress through the TAF period. The southern panhandle will primarily experience VFR flight conditions through the period with patchy/intermittent FG during the early morning hours today. There is no significant LLWS through the period. SFC winds will be strong/gusty for the northeastern Panhandle, including PAGY & PAHN, through the period due to northerly outflow gradient winds.

MARINE

Inside Waters(Inner Channels): Up to between around 35 & 40 kt gale force winds are likely for Lynn Canal down to the Point Couverden / Rocky Island area & around the Taku Inlet area into the weekend due to northerly outflow gradient wind conditions & peaking out just shy of gales down Stephens Passage to around Five Finger. For the rest of the N-S oriented Inner Channels, up to around 15 to 20 kt of wind are expected into the weekend. The E-W oriented channels will be around 5 kt lighter on average.

Outside Waters(Eastern Gulf of Alaska/Outer Coast): Up to gale force northeasterly outflow winds for the northeastern gulf coastal waters are possible into Friday. The rest of the eastern Gulf remains up to around 15 to 20 kt with a slight diminishing trend into the weekend. Significant wave heights between 5 & 10 ft with a diminishing trend are likely into the weekend.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Winter Storm Warning until 6 PM AKST this evening for AKZ317. Cold Weather Advisory until 6 AM AKST Sunday for AKZ318. Strong Wind through late tonight for AKZ318. MARINE...Gale Warning for PKZ012-013. Small Craft Advisory for PKZ011-021-022-031-032-053-643-644-651- 663-664-671-672.