Area Forecast Discussion
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
111 FXAK67 PAJK 051246 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 446 AM AKDT Wed Jun 5 2024 .SHORT TERM...One more day of active weather for the panhandle through Wednesday, before showers diminish on Thursday, with drier conditions by Thursday evening into Friday. A vertically stacked low continues to spin over the Gulf as of the time of writing. Model guidance has the low progged at 533 decameters as of the time of writing, with the low expected to steadily occlude and weaken through the day as it steers off to the NW. Before the low fully departs however, some additional waves will move through the panhandle. Operational model guidance has currently progged the primary low too far to the W, and so think that said waves will likely have stronger winds than previously anticipated. Continue to anticipate moderate to heavy rainfall rates (some areas could see in excess of an inch of rain), but while some rivers may approach bankful, no flooding is expected at this time. Conditions will improve Wednesday night onwards as the low departs, and the onshore flow weakens. The forecast remains largely on track, with the primary changes being to increase wind speeds across many land-based locations and for many of the inner channels. Strong wind are expected at times for places like Juneau and Skagway, along with elevated winds for maritime areas. .LONG TERM.../Thursday through Tuesday/... Overview: Rain showers and winds continue to diminishing early Thursday as remnants of previous front move out. Dry period as ridge builds in. Increasing likelihood that another low will enter the AK Gulf Saturday further to the east which brings in more rain and increased winds. The gulf low continues to pull back towards the Aleutian chain SE AK changes over the a dry period with calmer winds. High pressure ridge over the region develops Thursday into Friday. Warmer air moves in with 850 mb temps finally getting into the positives with temps of 6 to 10 C by Saturday. By the weekend there is the return of 500 mb low extending from the west. At the surface better indication for the development of a 985 mb gale force low and the eventual track into the AK Gulf from the south. Ensembles have better trend of the low center being further east but definitely not as strong as the operational GFS, which has been running a bit on the high side. However the GFS is further west than ECMWF, Canadian or most ensembles. The week continues with a an upper level low and series of surface features tracking into the gulf keeping a wet weather pattern going into the long range. Main forecast change was getting the low for Saturday and Sunday in. && .AVIATION...A low in the eastern Gulf of Alaska will keep persistent rain and overcast skies overspreading across the panhandle through the TAF period. Anticipating low-end VFR down to MVFR flight conditions through today for much of the area, with CIGs bouncing between 1500 and 5000 ft and intermittent VSBYs down to 4SM within the heaviest showers. Winds will remain elevated through the period for northern TAF sites, including PAJN, with sustained winds up to 20kts and gusts up to 30kts through at least 00z. Some LLWS will be persist across the northern panhandle TAF sites, but not high enough confidence to include in TAF at this time. Winds across the southern panhandle TAF sites will decrease after 00z to less than 10kts with potential for IFR cigs developing by 04z. && .MARINE...Small craft conditions will remain prevalent across the outer coastal waters through Wednesday night, and spread through the day on Wednesday across the inner channels. The strongest winds will likely be in the southern inner channels. Anticipate winds to begin diminishing Wednesday night, though Lynn Canal may hold out longer. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...Strong Wind from this afternoon through this evening for AKZ318. Strong Wind from 1 PM AKDT this afternoon through this evening for AKZ325. MARINE...Small Craft Advisory for PKZ011>013-021-022-031>036-641>644-651- 661>664-671-672. && $$ SHORT TERM...GFS LONG TERM....PRB AVIATION...NM Visit us at http://www.weather.gov/Juneau