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000
FXAK67 PAJK 192236
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
236 PM AKDT Fri Apr 19 2024

.SHORT TERM...Calm weather and clear skies continue this afternoon
across the panhandle. Temperatures continue to run warm this
afternoon with the clear skies. The clear skies are expected to
continue into tomorrow as high pressure starts to move to the
east. The best chance of seeing a pattern change to more cloudy
and wet weather looks to happen this weekend as a decaying front
approaches from the south. Guidance continues to slow down the
idea of precipitation and cloud cover for the area so changed the
forecast to reflect this. Temperatures will also raised for the
high tomorrow as well with the increased likelihood of seeing more
optimal warming during the day tomorrow. Currently, the best
chances of seeing any measurable precipitation will be across the
southern panhandle.

.LONG TERM...A shift in the pattern is underway in the long range
forecast, as more active weather returns to the panhandle Monday
and potentially through the first half of the week - though
active in this case means occasional chances of rain, rather than
any strong organized systems.

Aloft the ridge which has been over the panhandle is slowly being
shifted towards a more W/E axis as opposed to its previous N/S axis
as an impulse of energy begins building a trough along a similar W/E
axis to its south. Ultimately, this trough will succeed in advancing
N, successfully displacing the ridge on Sunday. This will bring with
it a weak occluding frontal band, and some chances of showers
across the area. The dynamics with the system don`t look all that
impressive, given a distinct lack of upper or mid level support,
and a lack of any significant amount of moisture. The possibility
of cyclonic vorticity advection along the trough axis contributing
to some enhanced precipitation (and possibly even an embedded
wave within the front), which could move into the southern
panhandle is a possibility. At this time though, that is far from
set in stone, as the trough - if it builds slightly more than
anticipated, could just as easily develop a wave which impacts
Canada more than it does SE AK.

Afterwards, rapidly growing disagreement in the operational
guidance, driven by the collapse of the organized steering flow
aloft over SE AK, necessitates a turn towards reliance on ensembles.
A low over the Central Gulf - associated with the advancing trough,
may attempt to veer inland towards SE AK. Should this happen,
anticipate precipitation to overspread the panhandle. Conversely, if
the low veers off in a different direction, SE AK could remain dry
for Monday, aside from a few showers, and potentially through the
remainder of the week. For the time being, chose to keep some
chances of showers in the forecast on Monday - but the potential
does exist for skies to be clearer than currently anticipated,
should the relevant low not move into the area, and offshore flow
take over. Confidence is starting to grow that Tuesday onwards,
may favor drier weather - along with corresponding clearer skies,
and greater diurnal shifts.

Made some changes to the sky and PoP grids to reflect the greater
potential for drier weather Tuesday onwards, along with some minor
changes to temperatures to increase the diurnal range.
Additionally did some work to reflect changes in winds based on
the drier weather.


&&

.AVIATION...
VFR conditions will persist across the panhandle with clear skies
and localized afternoon sea breezes through the TAF period. Winds
go near calm and variable overnight. Winds increase during the
afternoon, but should remain less than 15 kt with an isolated
gusts up to 20 kt possible.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ053-641>644-651-652-661>664-671-672.

&&

$$

SHORT TERM...SF
LONG TERM....GFS
AVIATION...NM

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