Area Forecast Discussion
Issued by NWS
FXAK67 PAJK 281310
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
510 AM AKDT Fri Oct 28 2016
.SHORT TERM...Another quiet short term period. Less wind than
yesterday, so have only small craft advisories for seas over the
eastern gulf coastal zones. Northerly pressure gradient is all but
gone, but there is a weak offshore component. Broken cloud cover
have prevented any widespread or dense fog. This has also limited
overnight lows and will prevent any significant warming today.
There are a few isolated showers over the central and northern
portions of the panhandle with scattered showers to the south.
These will dry up as the low over the southern gulf continues
tracking off to the southeast. Weak ridging at the surface over
the gulf will keep things quiet through Friday night as well.
Little in the way of changes made tonight apart from some
adjustment to overnight lows for Friday night. Warmed things up a
bit based on persistence and no significant changes to the airmass
in place. This was supported by GFS MOS. Still changes limited to
2-3 degrees at most. Overall forecast confidence is average.
.LONG TERM...The potential for snow re-enters the long term
forecast during the early to middle portions of next week. Model
guidance shows a midlevel ridge centered over interior AK
diverting strongest upper-level WLYS S of the panhandle region.
Meanwhile, a trough is forecast to dig SSW toward NRN BC Monday
and Tuesday. As this takes place, surface high pressure will
strengthen over NWRN Canada, and aid in locking subfreezing
boundary layer temperatures over the NRN half of the panhandle.
Accumulating snowfall will ultimately depend on low
predictability shortwave evolutions, and at this time, deterministic
model guidance shows an upper disturbance ejecting across the
SRN/CNTRL panhandle Tuesday night/Wednesday, which would yield
increasing UVVs/precipitation rates within a cold/subfreezing
airmass. Will continue to evaluate.
Besides possible snow, the combination of high pressure over NWRN
Canada and low pressure over the gulf will favor strengthening
offshore winds from Monday through Wednesday. Current wind speed
forecast will likely be bumped up during subsequent long term
outlooks as confidence increases in the evolving offshore pattern.
After Wednesday, multi-model consensus shows the upper flow regime
transitioning to SWLY. This will support a wetter and cloudier
pattern as a series of frontal waves moves across the region.
.AVIATION...Some pockets of patchy fog this morning. Otherwise VMC
conditions under a broken to overcast layer across most of the
panhandle. Light winds and no turbulence expected.
MARINE...Small Craft Advisory due to Seas for PKZ041>043-051-052.
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