Scientific Forecaster Discussion
Southeast Alaska forecast discussion
National Weather Service Juneau Alaska
340 PM akdt Thursday Jul 2 2015
Short term...the low continues to move inland to northwest
Canada. The surface ridging continuing to build across Southeast
Alaska and the eastern half the Gulf of Alaska. A large multi
center complex of low pressure south of the central and western
Aleutians will persist into Friday. Strong and gusty winds are
presently blowing through Lynn Canal and into the Skagway region.
Wind gusts of 40 miles per hour at Skagway are expected to persist in the
evening and then fall off to 20 to 30 miles per hour for the gusts.
Showers early over the Panhandle will taper off over night... with
a few showers lingering around and continuing to diminish to
isolated showers primarily along the coast mountain range by
Friday afternoon. Clearing sky cover over the southern Panhandle
through Friday so a little warmer and more sun there on Friday...
while the northern part will have to work a little more to develop
The Breaks for the sun.
The taku river will continue to subside tonight after the Glacier
dam outburst from lake no lake on Wednesday. Issued the final
Special Weather Statement on the event around 230 PM.
Long term...little change in thinking through much of next week.
Building ridge of high pressure over the Gulf will be the main
weather feature through middle week. Thereafter the ridge will
flatten out and shift east with a return to onshore flow by late
Clouds will be on the decrease across the Panhandle at the
beginning of the long range period on Friday night. This will be
short lived however as shortwave energy moves over the building
upper level ridge in the Gulf resulting in an increase in cloud
cover on Saturday afternoon. This will mainly be in the form of
middle and high level clouds...am not expecting any precipitation to
be produced by this feature at this point. For early next week the
ridge of high pressure will dominate the weather. 850 mb
temperatures will warm into the 15 to 18c range on Monday and
Tuesday. This combined with an inverted trough developing over the
southern Panhandle will lead to widespread 70s over the
Panhandle. Have bumped up temperatures for this time frame but
did remain a bit conservative for our inland locations especially
over the northern Panhandle. With this pattern would not be
surprised if these locations are able to reach the low to middle 80s.
Pattern begins to shift Wednesday into Thursday as the upper ridge
flattens out and shifts east. A weak piece of energy will push into
the eastern Gulf on Wednesday with increasing onshore flow...cloud
cover...and light rain chances for later in the week.
Used a blend of the 12z NAM/European model (ecmwf) through day 4 then the latest
wpc guidance for the remainder of the extended period. Changes to
the forecast were minimal and mainly limited to local effect
edits. Forecaster confidence is above average in warm and dry
conditions through middle week with onshore flow increasing
public...strong wind until 1 am akdt Friday for akz018.
Marine...Gale Warning for pkz012.
Small Craft Advisory for pkz013-022-031>034-042-043.
Small Craft Advisory due to seas for pkz041-051.
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