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FXAK67 PAJK 291359
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
559 AM AKDT Thu Jun 29 2017

.SHORT TERM...A busy weather pattern is upon us with a mid to
upper level warm front pushing its way over the northern Panhandle
this morning. The low center in the western gulf and its
associated front will start to influence the eastern gulf tonight.
Friday will bring a short wave along the front that will enhance
the rain to that could be heavy at times Friday afternoon and
evening.

The NAM was the front runner for timing and placement of the
precipitation. It slowed the advancement on Friday to the
overnight hours, so nudge the inherited forecast using the NAM.
Cloud coverage remains about the same with cloudy skies
dominating. There is a sliver of hope for some sunny breaks
this afternoon for the central and northern panhandle, east of Dry
Bay.

For wind and pressure issues the NAM and ECMWF showed good
agreement and initialized well. Adjusted winds in Northern Lynn
Canal to be a bit less this morning, but increased them for the
afternoon behind the mid to upper level warm front. Winds and
pressure changes where minimal elsewhere. Winds on the western
side of marine zone 52 will be approaching Gale Warning this
afternoon, but opted to keep them at SCA.

With a long fetch from the North Pacific into the gulf, the sea
state will build to 9 to 12 feet spreading across the gulf through
Friday.

.LONG TERM...Saturday through Thursday...As of 1030 PM Wed...A
shortwave originating from a parent upper-level low in the gulf
will begin to move east across the panhandle beginning early
Saturday. Precipitation will be ongoing Saturday along a
strengthening front moving onshore and is expected to continue
into Monday with greatest PoP values and highest QPF over the
central and southern zones. We increased QPF values for late
Saturday into Sunday and bumped up the PoPs using an SREF Ensemble
blend. For the beginning of next week, QPF was blended using GFS
and then blended with WPC for the later part of the time period.
We also continue to see multiple shortwaves will then continue to
impact the area into the through next week.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ022-041>043-051-052.

&&

$$

KV/Fritsch/Voveris

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