Area Forecast Discussion
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
730 FXAK67 PAJK 021333 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 533 AM AKDT Tue Jul 2 2024 .SHORT TERM...Rain remains in the forecast for SE AK through much of Tuesday, although drier weather is on the way for Wednesday. Satellite and radar imagery depict a weak wave slowly moving onshore as of the time of writing, bringing with it renewed periods of rain. The wave itself is relatively disorganized, with little in the way of well-defined thermal boundaries. Through the day on Tuesday, anticipate the greatest chances of precip to continue to be the coast mountains parts of the outer coast. Prince of Wales Island will see lower precip chances beyond the morning time frame as the main band of precip moves further inland. Chances of rain diminish through the evening and overnight time frame, before subsiding almost entirely across the southern half of the area by Wednesday. A ridge building east of a vertically stacked low over the western Gulf will help encourage clearing skies across much of the southern panhandle Tuesday night. Added chances of fog to the forecast for these areas as a result. Retained the possibility of haze for some locations due to smoke from wildfires in Canada. The primary changes to the forecast were some adjustments made to wind directions in the southern inner channels, strengthening winds across the Icy Strait Corridor, and increasing wind speeds for parts of the Gulf of AK and at elevation over the Coast Mountains. Made minimal changes to PoPs, and added chances of fog for the southern panhandle. .LONG TERM.../Wednesday through Monday/... Overview: Quiet weather for the mid range due to semi static mid level flow pattern through the start of the weekend. Increasing probability of rain for the end of the weekend into next week. At 500 mb: Closed low over the Western AK Gulf slowly dropping to the SE with weak ridging over the Panhandle. The low is expected to shift back N into next week with uncertainty on how far to the east it might shift. At the surface the gulf low stays to the west as it weakens limiting its impacts to the region. The surface ridge keeps onshore flow for northern half of the panhandle keeping chances of light precip and mostly cloudy skies in place. Ensembles show high probability of mostly cloudy skies. Operational models have more of a spread as NAM showing wide spread low cloud deck while GFS has skies lifting and more breaks developing by Thursday. Moderated temps where clouds remain but the southern areas warming into the low 70s due to solar heating. Warmer 850 mb air mass moves in by next week. Winds will be generally 10 kt or less initially except for the northern inner channels where the pressure gradient between the panhandle ridge and Yukon low will have increased southerly winds. Gulf winds pick up for the weekend as the surface low moves back north. && .AVIATION...From the overnight, any aviation limitations have been due to low clouds and lowered visibility centered around rain. When it`s not raining, conditions have been around high-end MVFR to VFR. But when the rain moves back in, conditions have been around IFR to low-end MVFR with isolated times of LIFR. LIFR conditions have been due to very low clouds. But once the rain moves on, conditions improved quickly. This kind of weather will linger around this morning with improving conditions this afternoon from south to north as a ridge of high pressure builds over the gulf. Some lowering is possible for the northern areas later tonight. && .HYDROLOGY... For the TAKU RIVER: The Taku River, after cresting at approximately 42.3 ft, is on its way down. Mariners in the region should watch for additional debris in the water over the next couple days. For the CHILKAT RIVER: Warm daytime and overnight temperatures have continued the melting of high elevation snowpack and glacier ice to produce minor flooding along the Chilkat River. Temperatures on Tuesday will be slightly cooler, allowing daily peaks to trend down, but remain above minor flood levels through Wednesday. If temperatures aloft stay cool, the river may fall below Minor Flood stage. However, temperatures are likely to warm back up for the start of next week. && .MARINE...No significant systems in the area, and a weak wave moving through on Tuesday will be replaced with a ridge of high pressure on Wednesday. Clouds are restricting sea breeze impacts however lesser versions are continuing. Anticipate wind speeds of 20 to 25 kt for parts of the outer coastal waters, the Icy Strait Corridor, Lynn Canal, and for some of the southern inner channels. Wind speeds will diminish to around 10 to 15 kt for many of the inner channels on Wednesday. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...None. MARINE...Small Craft Advisory for PKZ021-022-643-644-664. && $$ SHORT TERM...GFS LONG TERM....PRB AVIATION...GJS HYDROLOGY...Ferrin/GFS Visit us at http://www.weather.gov/Juneau