Marine Weather and Tide Forecast for Mud Bay, AK

SHORT TERM
/TONIGHT THROUGH SUNDAY/...
The low in the western Gulf of Alaska continues to shift northeastward and weaken, bringing a few more showery waves of precipitation into the panhandle. Most of these showers will be light compared to the heavy rainfall seen yesterday, however some areas along the outer coast and southern panhandle near Misty Fjords may see some more isolated thunderstorms pop up through the evening and into Saturday. The southern panhandle may see a brief break tonight in the showers, with much of the next rounds moving into the central and northern panhandle overnight into tomorrow morning, however precipitation chances will return across the south as well by tomorrow. Some patchy fog may develop over parts of the southern panhandle if there is enough of a break period between the showers, however there is not much confidence at this time. Showers and onshore flow will continue into Sunday as the low diminishes in the northern Gulf, however the precipitation chances will gradually decrease throughout the day Sunday.

LONG TERM
/Monday through Thursday/...
An active fall-time weather pattern will continue across SEAK next week. Monday will start off with a ridge of high pressure over most of the panhandle, which could lead to fog development, with weaker onshore flow and light showers ahead of the next system. A progressive low and cold front will trek across the Gulf and reach Yakutat Monday afternoon before sweeping southeast across the panhandle Monday night into early Tuesday before weakening and stalling across southern panhandle, with onshore flow behind bringing steady rain into the panhandle.
Total precipitation with this initial system will remain relatively limited, though a brief period of moderate to heavy rain and increasing southerly winds will develop ahead of the frontal boundary. Behind this initial system, a stronger low is forecast to deepen rapidly (~960 mb) as it lifts northeast into the northern Gulf of Alaska on Tuesday, stalling through midweek before gradually weakening and dissipating on Thursday. This strong low will quickly send another front and deeper moisture feed toward and through SEAK Tuesday into Wednesday, bringing moderate to heavy rain and strong gusty winds, along with severe marine hazards. South to southeasterly winds will intensify significantly on Tuesday, producing gale-force conditions in inner channels such as northern Lynn Canal and Clarence Strait, with gales (34-47 kt) and possibly storm-force winds (48–55 kts) and combined seas exceeding 20 feet along outer coastal waters, mainly from Cape Spencer northward. By Thursday, conditions will improve behind the frontal passage and as the low in the northern Gulf weakens, though lingering onshore flow will sustain rain showers, while winds and seas slowly subside.

Persistent onshore flow with mainly cloudy skies and rain will keep temperatures cool and consistent through the period, with daytime highs in the mid to upper 40s (low 50s possible on Tuesday) and overnight lows in the upper 30s to low 40s.

AVIATION
/through 06Z Sunday/...Isolated thunderstorm cells have been observed off the Gulf coast from Cape Fairweather northward this afternoon and evening, with a few tracking inland over the northern panhandle, though minimal impacts to TAF sites as convection has quickly dissipated. At most, some maturing cells could bring erratic gusty winds and heavier showers. As showers have moved out of the region, clear skies dominate across the central/southern panhandle. At the same time, a low south of the panhandle is sending some higher clouds over parts of SE Prince of Wales and Ketchikan keeping these areas generally fog free. The clearing over the central region has caused localized VSBY reductions due to low stratus and patchy fog settling near runways. However, given the lack of lower-level stability, widespread or prolonged impacts are not expected, with fog likely eroding between 12Z and 14Z as the next wave of rain showers moves into the region. This incoming disturbance will bring a more significant deterioration in conditions, as heavier showers reduce VSBYs and lower CIGs to 1000 feet at times. Nevertheless, most sites are expected to maintain predominantly high-end MVFR to low- end VFR conditions through the remainder of the current TAF period as active weather persists through the weekend.

MARINE

Outer waters: The low pressure system sitting in the northern gulf is swinging across yet another frontal system, generating 25-30 knot southerlies in the gulf waters through tonight. A shift to the southwest with similar wind speeds is expected during the early morning hours for the coastal zones before diminishing through Saturday night. Wave heights associated with the southwesterlies are expected to build to around 15 ft offshore between Cape Spencer and Cape Edgecombe. May also see some convective cells with some lightning strikes and stronger wind gusts. The low pressure, then vertically stacked, should slowly fill and move southeast, keeping up to 20 knot westerlies for Sunday morning before diminishing. Going into next week (Tuesday/Wednesday), a potent low moves into the central gulf, as noted in the long term section. Current guidance indicated a barrier jet looks to form along the NE gulf coast, generating storm force winds east of Cape St. Elias. Currently, there is good confidence on the strength of the system; however, confidence on timing and placement is moderate to low. There is evidence in ensembles that new low centers will generate along the negatively tilted shortwave aloft, which would move around the low. These types of scenarios would shift highest wind speeds much further down the coast, to around Cape Spencer at the furthest with current guidance. For waveheights, very strong southwesterly swell upwards of 22 ft will contribute to wave heights exceeding 25 ft in the gulf waters.
Stay tuned for more information regarding this system.

Inside Waters: Leading into the front, building high pressure in the southern panhandle in wake of the stronger front that moved through the southern portion of Clarence Strait may decouple winds. This combined with clearing skies and abundant moisture from recent showers may generate some fog overnight tonight ahead of the incoming front. The front from the aforementioned low pressure in the central gulf is expected to bring up southeast winds early Saturday morning to around 20-25 knots. Highest wind speeds, and associated small craft advisories, look to be for Lynn Canal and Stephens Passage. Definitely possibly to see an upgrade to 25 knot winds for northern Chatham Strait, but did not have the confidence for this forecast package.

HYDROLOGY
With the end of the larger atmospheric river system this morning, flooding concerns are no longer expected, even as some showers continue into the weekend. Rivers and creeks may still be at their crest into this evening, but overall most streams have crested by the morning / afternoon and all are expected to continue to fall into tonight and the weekend. Any showers that continue this weekend will be largely light, and even if some more productive cells bring periods of higher rainfall amounts, they will be quick moving and not persistent, with longer breaks between even the more organized bands of showers.

AJK WATCHES/WARNINGS/ADVISORIES
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ012-013-022-031-053-641>644-651-652- 661>664-671-672.