textproduct: Juneau

UPDATE

After 06z TAF issuance.

Forecast pretty much on track with previous thinking Did have some stronger winds push into the Yakutat area earlier in the evening so bumped up the winds in that area until about 12z with the wind ahead of the approaching frontal band, and bumped up the Wind shear in that region.

PREV DISCUSSION......ISSUED AT 355 pm Sat 9 May

SYNOPSIS...

Key Messages:

- Rain and breezy conditions continue through the weekend, with additional 0.5-1.5 inches of rain possible across SE AK.

- Improving conditions to start the week before more light rain moves in and spreads throughout the panhandle midweek.

SHORT TERM.../through Sunday night/...The gale force low continues to lift north through the Gulf, bringing with it breezy conditions and widespread rain. Multiple fronts/troughs will pivot around the low through Saturday night, bringing rounds of moderate to potentially heavy showers. On Sunday, as the low lifts north and weakens over the Kenai peninsula, rain will slowly diminish through Sunday night as onshore flow weakens and ridging builds into the region. Generally looking at additional rain accumulations of 0.5-1.5 inches through Sunday night, with upwards of 2 inches possible for some areas where heavier showers pass over. Breezy conditions will continue through Sunday. Winds could approach advisory criteria for Skagway and the Klondike Highway on Sunday as the low jumps ashore and the gradient becomes more south to north oriented. For now, gusts up around 35 mph look to stay just below criteria. Additionally, snow levels look to hover around 3.5-4kft through the period. However, snow levels could dip down to 3kft across the north and could bring snow or rain/snow mix near White Pass. A couple rounds of light slushy snow accumulations are possible during the nighttime and early morning hours through Sunday night.

LONG TERM.../Monday through Thursday/...The week opens with lingering precipitation from the outgoing system from the weekend. Current thinking is that showers will move out of the area by Monday night, leaving Tuesday to be cloudy but mostly dry with less than a 50% chance for scattered showers across the whole panhandle. The greatest chance for clearing skies is looking to be the southern panhandle during this time as a ridge of high pressure briefly moves in. The chance for precipitation is anticipated to increase late Tuesday night as a front moves into the northern panhandle associated with a low in the Bering Sea. Chances for precipitation in the southern panhandle look to increase overnight Tuesday into Wednesday as another pocket of moisture moves in over the gulf. Precipitation amounts are then expected to fall off again on Thursday throughout the day over the whole area. Rain this week is expected to be much more seasonable than those associated with the outgoing system. There are no flooding threats foreseen to be associated with the next bouts of rain.

Winds over this period are expected to be mainly light and variable in direction, with some defined wind shifts as the next front moves through. The winds in the gulf are expected to increase with the front, but the impacts are unlikely to make in to the inner channels. The strongest winds associated with the front are expected to be from just south of Yakutat Bay westward to Cape St. Elias. Yakutat could also see some higher winds primarily associated with the front passing through, about 10 to 15 mph.

AVIATION... A low pressure system in the Gulf of Alaska is bringing rain showers and gusty winds across Southeast Alaska. With the low pressure, we have seen showers develop with daytime heating and move to the northeast. The main impact with these showers has been lower ceilings, visibilities, and some gusty winds. As the low-pressure system approaches land, it will weaken, but it still will bring periods of MVFR generally south of Juneau. Tonight, Yakutat has concerns for LLWS. The low pressure system weakening should mean a decrease in the low level winds as well. However, chances for showers and rain will stick around through the TAF period. Exact location of showers leads to uncertainty on exact timing of category changes through the evening and early overnight hours. As the low dissipates and on shore flow develops, another round of afternoon showers are expected for the area. Again, there is uncertainty on the location of any showers and which specific taf sites they are most likely to impact Sunday afternoon. CIGs could get to AoA 1500 ft with passing showers.

MARINE... Inside (Inner Channels): As the gale force low continues to move northward through the Gulf, fresh to strong winds continue for the inaner channels through Sunday. Strong winds from the south expected to develop through Lynn Canal and Taiya Inlet by late tonight into Sunday as the low jumps ashore over Kenai peninsula and the gradient becomes more south to north oriented over the panhandle. Otherwise, winds will diminish into early next week as ridging builds over southeast Alaska.

Outside (Gulf and Coastal Waters): The gale force low continues to lift north through the Gulf, bringing gale force winds with gusts up to 45 kts over the eastern Gulf and northeast coastal waters through this evening. Associated with this system is an excellent dynamic fetch responsible for southerly swell, along with the aforementioned fetch of southeasterly winds generating large southeasterly wind waves along the coast. Expect large and confused seas of 15 ft or higher, to potentially as high as 20 ft, along the majority of our coast through tonight, with the focus of wave energy from the Fairweather Grounds to Cape St. Elias. Winds and seas decrease dramatically on Sunday as the low jumps ashore and weakens over the Kenai peninsula. The next low riding along the Alaskan peninsula looks to bring elevated winds and seas Monday night into Tuesday for the northern coastal waters.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Wind Advisory until 4 AM AKDT Sunday for AKZ317. MARINE...Gale Warning for PKZ644-651-652-663-664-671-672. Small Craft Advisory for PKZ012-013-021-022-031>033-036-053- 641>643-661-662.