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FXAK67 PAJK 221232
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
432 AM AKDT Wed May 22 2024

.SHORT TERM...
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Forecast updates:
Decreased PoPs over portions of Panhandle Wednesday. Increased easterly
winds out of Cross Sound and Palma Bay.

Early this morning satellite derived winds highlighted a triple
point low east of the Alaskan Peninsula, which will impact
weather in our region over the next 48 hours. The main threat
Wednesday is the increase of southeasterly winds along our coastal
waters, which will drive an increase in southeasterly fresh seas;
however, expect stronger winds and seas near classic locations
like Cape Fairweather and Cape Suckling. After the front hits the
Panhandle Wednesday night we will see 20 knot westerly winds fill
in across the Gulf.

Regarding precipitation, IVT forecasts from the Center for
Western Weather and Water Extremes highlight limited duration and
magnitude of IVT; furthermore, current CMORPH satellite rainfall
rate analysis of the developing low continue to look unimpressive.
For timing, Wednesday expect light rain showers in the north with
heavier rainfall filling as the front moves over the region
Wednesday evening. 24 hour totals will come in around 0.5 to 1
inches, enough to bump up some areas to their monthly May normals.


.LONG TERM.../ Wednesday through Saturday night / Active pattern set
to continue for SE Alaska for the remainder of the week. The next
system will move into the northern Gulf on Wednesday, with a
weakening front making its way towards the panhandle Wednesday
afternoon and slowly push inland through Thursday. While not an
impressive system, tightening of the pressure gradient near shore
will still lead to winds of 25 to 30 kt for the Northern and NE gulf
coast for a time Wednesday afternoon into Wednesday night.
Consequently not expecting to see any significant wave height
increases.

Total precipitation from this system has been trending upwards
slightly, but overall is still expected to be light to moderate by
SE AK standards, with most rain coming Wednesday night into Thursday
morning. Storm total QPF for the panhandle ranges from around 0.75
inches for the northern Gulf coast to around 0.5 inches from the Icy
Strait Corridor southward. Once the rain moves through and
accompanying low diminishes into a weak open trough, skies are set
to clear later in the day Thursday and into Friday. This will allow
for potential fog development in areas which can see maximized
radiational cooling in the overnight hours along with light winds.

Clearing skies on Friday means warmer temperatures once more, with
daytime highs rebounding back to upper 50s and near 60 for the
majority of the panhandle heading into Saturday. Unfortunately
unsettled weather looks to move in once more for the second half of
the holiday weekend with increasing rain chances Saturday afternoon
into Sunday.
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&&

.AVIATION...
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Aviation weather is fairly quiet this morning with VFR
conditions prevailing just about everywhere (Exception: Rain has
already started at Yakutat with ceilings down to 1500 ft this
morning). Winds are light as well. Conditions will start to
degrade later today into tonight as a new front moves in from the
W. Rain will begin from W to E with ceilings descending to MVFR
conditions tonight (possibly as low as IFR in some isolated
areas). Winds will not be that significant with this front though
some turbulence may be encountered. Conditions overall expected to
gradually improve Thursday into Friday.
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&&

.MARINE...
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Gulf and Coastal waters: Elevated southeasterly winds impact the
Gulf and coast Wednesday, with 20 to 30 knots of wind and fresh
seas of 8 to 11ft. Mariners transiting near Cape Suckling and Cape
Fairweather will see stronger winds, perhaps a brief and isolated
period of gale force, increasing significant wave heights a touch.

Inner channels: Over the next 36 hours main threat remains near
ocean entrances like Cross Sound, Chatham Strait around Pt.
Gardner south, and western Sumner. Have increased easterly winds
for Cross Sound to 20 to 25 knots Wednesday as the low moves in.
Mariners operating in southern Chatham and Clarence Strait will
see 15 to 20 knots of southerly winds fill in Wednesday late
afternoon and overnight. Full moon is Thursday, will see larger
tidal swings and resulting increase in currents, bringing slightly
higher seas in isolated areas.
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&&

.AJK WATCHES/WARNINGS/ADVISORIES...
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PUBLIC...None.
MARINE...Small Craft Advisory for PKZ642>644-651-652-662>664-671-672.
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&&

$$

SHORT TERM...AP
LONG TERM....STJ
AVIATION...EAL
MARINE: AP

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