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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

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