Area Forecast Discussion
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
685 FXAK67 PAJK 041427 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 527 AM AKST Mon Nov 4 2024 .SHORT TERM.../Through Monday night/ Quiet morning across the panhandle as most of the area is caught between two systems. One low is south of the panhandle over Hecate Strait and heading into British Columbia. The other is the dieing low near Prince William Sound. Between the two is onshore westerly flow and scattered showers. Generally the quiet weather is expected to last through Monday night as a flatter ridge builds in from the west across the Gulf. Showers across the panhandle are expected to linger today (with a lingering slight chance of thunderstorm along the NE Gulf coast this morning), but diminish in frequency and intensity Monday night. Signs of change are coming late tonight across the gulf however, as the initial effects of the next front start to make them selves known. Winds will be increasing to gale force and the initial rain bands will be moving in to the central gulf by late Monday night. The current forecast has suggested a faster speed to the next front by around 6 hours or so compared to the previous forecast mainly due to the front being pushed east by a 120 kt 500 mb jet. Even with that increase in frontal speed the winds and rain with it are still not expected to arrive in the panhandle until Tuesday. .LONG TERM.../Tuesday through next week/...The forecast for this week remains largely unchanged. The big story will be the heavy rain across parts of the panhandle Tuesday through Friday as a series of systems move across through the area. The first system - a storm force front - will weaken as it enters the panhandle on Tuesday, though still anticipate strong winds for many communities, especially those along the outer coast and in the southern panhandle. A trailing atmospheric river in the wake of the system will move across the southern panhandle Tuesday and Wednesday, bringing with it widespread heavy rainfall. Amounts of between 1 - 2 inches of rain are expected near sea level on Tuesday across the southern half of the panhandle, with 2-5 inches for Wednesday. Another system racing northward will bring with it an additional 0.5 to 2 inches of rain for Thursday, and higher rainfall totals in general are possible for areas of elevation. Lower rainfall totals are expected for the northern half of the panhandle. The primary concern with this event is primarily rainfall duration as opposed to rainfall rate. River rises are anticipated, but no flooding is expected at this time, although the situation will be closely monitored in the event that updates become necessary. With regards to the potential for snowfall, anticipate that it will be confined to the Haines and Klondike Highways for any snow or snow dominant mix when precip from the first front arrives. Overall expecting temperatures aloft to warm up enough to limit snow accumulation aside from near the Canadian border, with substandard lift and less favorable snow ratios likely to help cap snow totals, though this will need to be monitored and evaluated further over the next few days. Winds in the outer coastal waters and across ocean entrances will reach gale force intensity, with a few areas in the central gulf and the northern gulf reaching storm force as the first system arrives. Winds in the inner channels will pick up to small craft on Tuesday, before diminishing across the northern and central inner channels to some extent on Wednesday. && .AVIATION...Conditions continue to improve as rain exits the panhandle. We will continue to see times of MVFR through this morning into early afternoon before all areas improve to VFR ceilings and visibilities. With the departing rain there is a higher chance of seeing areas of broken fog during the morning hours. Decreasing winds and breaks in the clouds will also help to increase fog chances. Locations with fog will most likely stay MVFR, but could decrease to IFR ceilings or visibilities for short periods of time. && .MARINE...Quiet marine weather through Monday evening then the effects of the next front will start making themselves known. Winds across the gulf expected to increase to gale and even storm force (northern gulf) late Monday night into Tuesday and those winds will spread into the inner channels by Tuesday afternoon. Expect widespread 25 to 30 kt winds in the inner channels with a few areas likely seeing gale force winds as well. Seas in the gulf will be on the increase with this front, likely reaching 20 ft Tuesday afternoon. Initial front moves through rather quickly and winds and seas are expected to diminish area wide by late Tuesday night. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...None. MARINE...Gale Warning for PKZ652-672. Small Craft Advisory for PKZ022-053-641>644-651-661>664-671. && $$ SHORT TERM...EAL LONG TERM....GFS/STJ AVIATION...EAB Visit us at http://www.weather.gov/Juneau