Marine Weather and Tide Forecast for Whale Pass, AK

SHORT TERM
/through Saturday night/ Forecast remains largely on track as snowfall this morning as gradually increased in coverage and intensity overnight with visibilities decreasing down to 1 to 2SM as of 6 AM AKST. Adjusted approaching storm track and the near-term snowfall totals through early morning to reflect estimated accumulations across Juneau, Gustavus, Hoonah, and Tenakee Springs, with around 3 to 4 inches fallen at the WFO overnight. These overnight accumulations are separate from the next system set to affect the area through Saturday as a compact low traverses NE across the Gulf and into the central panhandle. As the low center tracks inland through Saturday afternoon and evening, south to southwest wind will cause temperatures to warm over the southern outer coast with a mix or change to rain. Snow will then end on the NW side of the low, from Sitka to Juneau northward Saturday night. Winter storm warnings and advisories are in effect for Gustavus to POW and Hyder through Saturday night for majority of SEAK and by Sunday afternoon for Hyder. Snow will end on the NW side of the low, from Sitka to Juneau northward Saturday night. Areas to the north (Yakutat, Haines, Skagway) are currently expected to see less than 2 inches on Saturday. For the Ketchikan and Metlakatla areas, 1-3 inches of accumulation is possible before they see mixing with rain Saturday afternoon. Strongest winds gusts up to 35 to 40mph will remain just south of Sitka towards tip of southern Baranof Island eastward towards N Prince of Wales Island and into Stephens passage by Saturday evening, however can't rule out an isolated gust working northward.


LONG TERM
/Sunday through Wednesday/ Winter continues to flex its muscles this weekend and into early next week with more snow and cold temperatures. An upper level trough over the interior will help to anchor high pressure at the surface and drive colder continental air into the northern inner channels. While the surface ridge does not look to be excessively strong (around 1040 mb), the important thing to note is the upper level support and overall staying power. This upper level pattern will also steer more storms and short wave features into the panhandle overall, being a classic setup for overrunning to bring ample snow to a majority of the panhandle. After the first influx of snow impacts the panhandle Saturday, there will be a brief lull and/or decrease in rates, particularly for the northern panhandle, before it ramps up again Sunday into Monday. The key question, particularly for Sunday into Monday, is how far south the arctic boundary stays entrenched.

There is relatively good model agreement on this boundary setting up in the vicinity of Sumner Strait by the start of the long range forecast period and hovering around that area to start the week. Wavering of this rain snow line could lead to highly variable snow amounts as well as snow characteristic in terms of being light and fluffy or wet and otherwise harder to deal with.
While communities north of Sumner Strait will likely see light and fluffy snow throughout this period, Petersburg and Wrangell as well as northern parts of Prince of Wales Island will be watched very closely in this regard. A winter storm watch has been issued for Petersburg and Wrangell as they remain in the cross hairs for the tail end of the first batch of snow mentioned in the short range discussion, and another surge of moisture Sunday afternoon into Monday.

South of Sumner Strait, a quick transition to a rain snow mix and rain is expected with very little to no snow expected at this time for Annette Island, Ketchikan, and southern Prince of Wales Island. This will be looked at in greater detail and adjusted as necessary based upon how the forecast plays out with the arctic boundary on Saturday.

For the panhandle north of Sumner Strait, temperatures and dew points are expected to remain low enough to maintain snow throughout the period, and likely be lighter and more fluffy.
While the heaviest snow rates are expected to impact the central panhandle, light to moderate snow will slide northward through the beginning of the week. Stay tuned for further forecast updates for this active pattern.

AVIATION
/through 12z Sunday/ As of 0600 AKST Saturday morning flying conditions around the Panhandle are generally poor from westerly snow shower activity; quickly becoming widespread snow. The clear winner for VFR is the northern coast as the system transits south and east. For the rest of the Panhandle, IFR will be the theme Saturday from VSBY less than 2SM, with CIGS below 1000 ft at times. Under heavier bands of snow, we will see LIFR, with VSBY at or below 1/2SM and VV005.
For areas along and south of Sitka/Petersburg there will be a transition to +RA Saturday late afternoon, with VSBY improving to MVFR. Folks north of this line will likely continue to see IFR to LIFR from snow until later Saturday night. A band of westerly winds of 40 to 50 knots at 5000 ft will bring some OCNL MOD OR GTR TURB (as advertised by the AAWU) in the central and southern Panhandle, with westerly LLWS of 30 knots or so for southern TAF sites starting near 1400 to 1600 AKST Saturday.

MARINE
Outside (Gulf and Coastal Waters): A compact low will traverse NE across the Gulf towards Baranof Island and inland through Saturday afternoon. This low is expected to bring fresh to strong breezes to the Outer Coast along with a building sea state. Seas are expected to build up to 10-14 ft south of Cape Edgecumbe as this next low moves into the area.
Potential for a small area of Gale force winds off the southwestern coast of Baranof as low tracks inland. near Farther north, seas are expected to be less significant. The swell direction is expected to remain out of the S-SW direction during this time. Another low is expected to move into the area Sunday into Monday bringing more active weather to the outside waters.

Inside (Inner Channels): Winds in the Inner Channels are expected to get up to fresh breezes to near Gale with this next system for Saturday into Sunday. Near gales to gale force northerly winds with moderate to heavy freezing spray is expected within Lynn canal Sunday afternoon as winds increase. Elsewhere, some pockets of gales remain possible, especially through areas of narrow terrain or known gap flow areas. Snowfall will increase in coverage and intensity through Saturday afternoon and into the evening, periods of visibilities below 1 nm expected within any moderate to heavy showers. With an Arctic boundary expected to set up, parts of the Inner Channels will be out of the north while locations to the south of this boundary will be out of the south as this next system approaches. Another low is expected to move into the area for Sunday into Monday which will bring more active weather to the Inner Channels.

AJK WATCHES/WARNINGS/ADVISORIES
PUBLIC...Winter Storm Warning until 9 PM AKST this evening for AKZ320>322.
Winter Weather Advisory until 6 PM AKST this evening for AKZ323.
Winter Weather Advisory until 9 PM AKST this evening for AKZ324- 327-328.
Winter Storm Warning until 11 PM AKST this evening for AKZ325- 326-329.
Winter Storm Watch from Sunday morning through Monday morning for AKZ326-329.
Winter Storm Warning from noon today to noon AKST Sunday for AKZ331.
MARINE...Gale Warning for PKZ662.
Small Craft Advisory for PKZ012-013-031>036-641>644-651-661-663- 664-671-672.