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fxak67 pajk 271316 

Southeast Alaska forecast discussion
National Weather Service Juneau Alaska
516 am akdt Mon Mar 27 2017

Short term...low pressure west of haida gwaii will weaken as it
continues to move north-northwest towards the north central Gulf Coast today.
Precip has made it as far north as Frederick Sound this morning and
will continue to expand nwd through the morning. Temps over the
northern Panhandle are cool enough that precip may begin as snow
early before transitioning to rain later this morning. Little to no
accumulation expected outside of The Klondike and Haines highways
where 1-2" are possible this morning. This low will maintain small
craft advisories for winds over the Gulf, Cross Sound and
Clarence Strait through this afternoon before winds ease ahead of
the next system, however, advisories for seas will persist over
the Gulf into Tue. Model solutions in good agreement today but
diverge regarding another low deepening SW of haida gwaii
overnight into Tuesday. Models in fairly good agreement with
placement of low over the central Gulf, but differ in strength
slightly. Main differences are with the low approaching the
southern Panhandle from the SW overnight into Tue. Gem was
strongest with this low/ec weakest furthest S/GFS/NAM in fair
agreement on strength but differed on timing with NAM quicker to
move this feature through. Overall, precip will transition to
showers from S to north late this morning/this afternoon. Pops will
increase again Mon evening into Tue as the next system approaches.
Ptype will be liquid across all but the north Panhandle where snow/mixed
precip is possible overnight. Used NAM/GFS blend to update inherited

Long term...
there remains a lot of details that still need to be worked out
especially in the Tuesday through Thursday time frame. One item
that does seem to have increased in confidence is the approach of
a front to the eastern Gulf Coast Tuesday into Tuesday night
which will be stronger than previously thought. Right now it looks
like it will Manly bring Small Craft Advisory level winds, but
there remains a possibility they could kick up to Gale Warning
levels as well.

The overall pattern will bring in a bit of precipitation to all
of Southeast Alaska but the nature of these individual lows that
develop around the low complex over the Gulf of Alaska make it
difficult to resolve the actual tracks much in advance. This
situation actually improves as far as forecasting confidence GOES later
in the week when a much stronger low moves into the western Gulf
of Alaska and consolidates the diffuse energy around these
smaller lows into the one larger low.


Ajk watches/warnings/advisories...
Marine...Small Craft Advisory for pkz022-036-041>043-051-052.
Small Craft Advisory due to seas for pkz053.


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