


Area Forecast Discussion
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
012 FXAK67 PAJK 090600 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 1000 PM AKDT Tue Jul 8 2025 .UPDATE...For Insertion of the 06Z Aviation Section... && .SHORT TERM...Conditions across the panhandle remain rather damp and grey Tuesday afternoon, with some locally heavy showers moving through the central and southern panhandle earlier in the day. An upper level trough will continue to move eastward Tuesday night, before s surface ridge builds in over the panhandle form the south into Wednesday. Some cloud breaks tonight as showers diminish and allow for radiational cooling and lower overnight temperatures heading into Wednesday morning, with isolated patchy fog possible. With persistent onshore flow, coastal communities could still see an isolated shower Wednesday due to orographic effects, but overall precipitation chances fall throughout the overnight period into Wednesday with the departure of the upper level trough. With the ridge building in on Wednesday, conditions across the panhandle will be relatively benign, with the exception being areas that could see stout sea breezes such as Lynn Canal up to Taiya Inlet. For Wednesday night into Thursday, light winds combined with less cloud cover could see more patchy fog development, particularly further inland from the coast, ahead of an approaching gale force front late Wednesday into Thursday. For more information on the next impactful system later this week, see the long term discussion. .LONG TERM... Key messages: - Surface ridge gets pushed out by approaching low in the gulf - Atmospheric river brings moderate to heavy rain Thursday - Gale force winds along the NE coast and near Dixon Entrance Details: The main long term impact will be the atmospheric river funneling moisture into the panhandle Thursday into Friday. The ridge over the panhandle will continue getting pushed eastward by a surface low pressure system with an upper level low in the western gulf. With the help of the upper level jet, the associated warm front will reach the panhandle through late Thursday morning, fueled by a large plume of increased moisture from a moderate atmospheric river. This system is expected to bring widespread moderate to heavy precipitation through Thursday afternoon. Highest rates will occur Thursday night into early Friday morning, with a majority of areas (mostly in the southern panhandle or along the coast) seeing potential for 1.5 to 2 inches of rain in this period. Sustained gale force winds of 35 to 40 kts are expected toward the NE gulf with the strongest winds off the coast of Cape Yakataga. The rest of the eastern gulf coast will still see increased winds to strong breezes of 25 to 30 kts along the outside marine waters. Inner channels winds increase up to 30 kts with the strongest at ocean entrances and in Clarence Strait near Dixon Entrance. Land areas in the southern panhandle and off the coast of Yakutat could experience wind gusts around 35 mph. Confidence continues to increase in the strength of the AR with multiple IVT ensembles showing the likelihood of a magnitude of >500 kg/m/s of integrated water vapor transport, a moderate atmospheric river, moving over the panhandle. EFIs are indicating a high QPF potential for the southern panhandle with a shift of tails of 2. NBM guidance is indicating much higher amounts of precipitation than initially expected, leading the decision to increase amounts for areas of the southern panhandle to >0.5 inches of rain in 6 hours. In 24 hours, areas across the panhandle will receive 1 to 2 inches of rain, with southern Baranof Island and higher elevations receiving up to 3 inches. Currently, no flooding impacts are expected, but increased snow levels with heavy rain rates can lead to rises in rivers and creeks to bank full. Active weather continues for SE AK into next weekend as onshore flow with a few embedded shortwaves keep the panhandle damp. Stay tuned as we will continue to update the forecast ahead of this system. && .AVIATION...Until 06Z Thursday/...As far as CIGs & VISs, a mix of MVFR & VFR flight conditions this evening will give way to a mix of MVFR & IFR category conditions overnight. Conditions should be improved to within the VFR category by Wednesday afternoon as the current weather system continues to depart the area & a ridge builds-in over the eastern Gulf & Panhandle region. As far as SFC winds, rather breezy/gusty conditions out of the south are in store for the entire TAF period for the northern Lynn Canal region, including PAGY & PAHN, as a relatively tight south to north oriented pressure gradient will remain in place over that area. LLWS values appear rather benign across the entire region through the period. && .MARINE... Inside waters: As a surface trough over the northern inner channels shifts off to the east today, high pressure will build in from the south. Southerly winds have increased through the day, with strongest winds being observed along Lynn Canal. The ridge will be quite flat for the next 24hrs, leading to a general W wind, which means some N-S passage wind directions will want to kink either NW or SW, or become variable <10kt. Sunny breaks will enhance sea breeze winds in the afternoon and early evening Wednesday. Outside waters: Generally west winds of around 15 kt as ridge builds in from the southeast. Seas still remain on the low end with gulf buoys reporting 4 - 5 ft combined seas and a S swell with a 15 second period. Expect seas of 4-6ft to persist until a stronger front approaches late Wednesday night and winds increase to gale force (+35kt) out of the southeast by Thursday morning. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...None. MARINE...Small Craft Advisory for PKZ012. && $$ SHORT TERM...STJ LONG TERM....ZTK AVIATION...JLC MARINE...STJ Visit us at http://www.weather.gov/Juneau