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104
FXAK67 PAJK 272218
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
218 PM AKDT Tue Jun 27 2017

.SHORT TERM...Tuesday night through Thursday night...A high
pressure system located across the central Gulf will move inland
tonight. A low pressure system will move into the southwest gulf
by Wednesday night. A series of short waves will spiral around the
low pressure system advecting moisture across portions of the
panhandle this week. Chances for showers will increase across the
northern panhandle tonight. Mostly cloudy skies will prevail
across most of the region the next few days. Models remain in good
agreement today.

Small craft advisories will prevail across Northern Lynn Canal
through this evening.

By Thursday models stay in good agreement with minor differences in
advancing the precip into the panhandle, with the NAM being slower
and more conservative to bringing it onshore than the others. Timing
of the healthy precip with the associated front is early Thursday
morning west of Yakutat and then will spread southeast across most
of the panhandle through the day.

Temperatures will be a bit cooler on Thursday for the max
temperature as clouds will have returned to a substantial thick
overcast layer. On the flip side the Thursday night lows will
generally be a few degrees warmer, with less loss due to radiational
cooling.

Winds over land will stay generally ranging around 5 to 15 mph with
a southerly flow. Inside waters follow suit with winds around 10 kt
or less, with the exception of the north-south orientated waters
with 10 to 15 kt. The strongest winds will be on the outside waters
with 30 kt small crafts moving across the gulf and then falling
short of the outer coastline and diminishing.

.LONG TERM...Friday through Tuesday...As of 1000 PM Mon...An
upper level ridge located east of the southeastern Alaska region
with an associated surface high pressure will remain over the
area, influencing conditions for Friday into Saturday. Deep layer
onshore flow and plenty of moisture will fuel a sustained cloud
low level deck. Multiple shortwave troughs will then progress east
out of the gulf, originating from a broad area of low pressure
located over the central gulf, impacting the region through this
weekend. Long range models are in general agreement for
accumulating amounts of precipitation through this weekend into
Monday. As the systems make their approach, timing of
precipitation will become clearer. PoPs were analyzed using mainly
the GFS model ensemble and then trended more with WPC guidance.
Pressure and wind updates blended towards GFS through Friday, then
towards WPC through the remainder of the long range period.
Overall confidence is average.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ012.
     Small Craft Advisory due to Seas for PKZ051-052.

&&

$$

BM/Fritsch

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