804
FXAK67 PAJK 311444
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
644 AM AKDT Fri May 31 2024

.SHORT TERM...Twin frontal bands moving into the panhandle
through the day on Friday will bring with it widespread rain and
wind for SE Alaska, with the heaviest rainfall totals and
strongest winds located primarily in the southern half of the
panhandle.

As of the time of writing, satellite imagery depicts a low over
the central Gulf, along with two separate fronts - a warm front
and a corresponding cold front which has largely caught up with
it, and which have already begun to advance into the area. This
system will bring gale force conditions to many of the outer
coastal waters, but the actual front(s) themselves will have
significant difficult moving beyond the central panhandle through
the day on Friday, in large part because of their distance from
the primary low, and said primary low`s own fairly slow advance
northward. A lack of impressive support aloft - what divergence is
present will diminish with time and pales in comparison to the
primary band of jet stream winds which remains S of the panhandle,
will contribute to a weakening of the system as it moves through.
At this time, am expecting small craft conditions for some of the
southern inner channels, and breezy conditions for some land-
based locations, but strong winds will likely remain largely
confined to the Outer Gulf Coast.

By Friday night, the system will have finally reached the northern
half of the panhandle in full force, although it will be
significantly weaker by this point. A relative lull with more
showers than stratiform precip is possible for Saturday before
another wave begins moving up on Sunday. The primary changes to
the forecast were some refinements to wind speed and directions as
well as increased PoP chances for the Icy Strait Corridor.

.LONG TERM.../Saturday through Friday/ Extended period remains
rather active as a broad upper trough remains in place over the
entire state through next week at least. Add on to this the upper
lows that will nearly be a semi-permanent feature in the gulf
over the next week and what you get is periods of wet weather with
the occasional stronger system being the norm across the
panhandle and Gulf of Alaska for the extended period.

There are three systems of note through the extended period: the
remaining gulf low from Friday`s system which will mostly affect
the N central gulf, A stronger trough moving through on Sunday
mainly aimed at the southern panhandle, and a low that has the
remains of a former tropical system (Tropical Storm Ewiniar)
expected for Tuesday thru Thursday of next week. All of these
features have wind (mostly 20 to 30 kt) and rain associated with
them, but it is the third feature, the one with the tropical
cyclone remnants, that will be watched more carefully as it has
the potential to be more wet and windy then is currently depicted.
It also is the system that affects more of the panhandle then the
other two in the extended period. As of right now, that system
appears to track across the northern Pacific on Monday before
rotating up into the Gulf on Tuesday. Being a former tropical
storm there is a decent amount of moisture that is embedded in the
system. However, most of that moisture appears to be aimed
farther south toward British Columbia. Still there is some
moisture transport that will bring some of that precip northward
into the panhandle, and I can not rule out some heavier rain bands
either, so mid next week is looking wet especially for the
southern panhandle. Winds will be watched too with 20 to 30 kt
winds expected across the southeastern gulf and parts of the inner
channels. Gales could also be possible for the southeast gulf and
southern panhandle early Tuesday. Typically guidance in the past
has had trouble depicting where former tropical systems might go
after becoming extratropical, but they are starting to reach more
of a consensus on this one. We will be watching this for any
further developments as we get closer to the event.

&&

.AVIATION...Incoming weather front spreading rain into the southern
panhandle along with ceilings in the 1500 to 2500 range. Remainder
of panhandle starts in the VFR category.  As the front moves through
during the day and into the evening, expect to see more widespread
Ceiling lowering into the 1000 to 3000 foot range.  Flight
visibility`s lowering some as well. While local IFR conditions may
develop think those will be spotty.  Likely biggest issue to
aviation today will be the winds with the front causing turbulence,
and even some Low level shear the band of winds around 3000 ft
should be max out round 30 to 40 kt, on the outer coast through late
this afternoon.

&&

.MARINE...Gale force winds for the outer coastal waters and small
craft conditions for some of the southern inner channels and ocean
entrances will occur through the day on Friday. Conditions will
improve somewhat Friday night, though elevated winds across the
inner channels are expected to remain prevalent.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 4 PM AKDT this afternoon for AKZ323.
MARINE...Gale Warning for PKZ644-662>664-671-672.
     Small Craft Advisory for PKZ022-033-035-036-053-641>643-651-652-
     661.

&&

$$

SHORT TERM...GFS
LONG TERM....EAL
AVIATION...Bezenek

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