Gale Warning 215, NWS Juneau, AK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
340 PM AKDT WED SEP 7 2016

.SHORT TERM...An upper-level shortwave trough is in the process of
exiting east-southeast away from the panhandle. Modest midlevel
ridging will occur in its wake, yielding a generally subsident
large-scale regime, which when combined with recent rainfall and
weakening low-level winds, will favor patchy fog tonight.
Otherwise, showers will be possible across the panhandle through
Thursday afternoon. However, subsidence beneath the previously
mentioned ridge is expected to limit shower coverage and
intensity. Meanwhile, small craft westerlies occurring over Dixon
Entrance will weaken this evening, and small craft seas over the
southeastern gulf will subside as well.

.LONG TERM.../ Thursday night to Wednesday / The main excitement
for the time period is happening Thursday night into Saturday. The
developing system, which has pulled in some of the energy and
moisture from former Hurricane Lester, will move into the central
Gulf of Alaska Thursday Night. It seems the triple point feature
will be racing ahead and is expected to move across the southern
Dixon Entrance area by early Friday. Meanwhile the occluded front
moves northward over the panhandle during the day.

Winds with the initial front suggests a band of gale force winds
near the front. The tightening of the pressure gradient with the
front will increase winds through Clarence/Sumner/Southern Chatham
Straits and Cross Sound up to gale force Thursday night with gusty
winds through the adjacent marine and land zones as well. Did not
headline for strong wind of 40 mph or higher, however this will be
reviewed on the next forecast package to confirm or lower the gusty
winds for the exposed capes and channeled areas.

Additionally, as the upper level feature and the wrap around band
moves closer to the coast on Friday, there seems to be sufficient
instability that more serious convection could occur. Thus have a
small pocket of thunderstorms with that.

Post frontal band of strong westerly wind forms over the central
gulf of roughly 30-35 kt Friday and Friday night. This should
develop an area of higher seas of around 15 to 22 ft to travel
towards the southern panhandle Friday night.

A ridge building Saturday into Sunday over the gulf should lead to a
day or so break in the clouds and precipitation for Sunday.
As the ridge axis becomes positively tilted headed into next week
with good flow across the gulf, look for the development of an
atmospheric river by midweek to move south across the panhandle.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ041>043.
&&

Garner/Bezenek

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