Area Forecast Discussion
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FXAK67 PAJK 262302
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
302 PM AKDT Wed Jun 26 2019

.SHORT TERM...The latest satellite imagery shows most of the
panhandle under mostly clear skies with a large area of marine
layer stratus over the Gulf of Alaska. There is also areas of
convection in Canada that is producing lightning near the Haines
Highway, Klondike Highway and approaching the Hyder area. Some of
these thunderstorms may make it across the border and affect
those areas with temperatures in the upper 70s to lower 80s. Winds
across the area are on the lighter side from the north. The
exception are the westerly winds from 15 to 25 kt near Cross Sound
to Icy Strait. The westerly winds will slow to decrease but
should be less than 10 kt by late tonight. The northerly winds
will increase in Lynn Canal with a inverted trough strengthening.

The marine layer will begin to move back into the coastal area
tonight with some being advected into Sumner Strait and then down
into Clarence Strait with the north winds from the inverted
trough. So there maybe some areas of fog for those areas affected
by the marine layer. The marine layer will begin to get pushed
offshore through Thursday as the mid-level flow backs around to
the NNE.

The area will see near record temperatures Thursday and possible
Friday as a very warm airmass moves over the area along with
increased adiabatic warming from deep easterly winds up to 10k
feet. Most of the inner channels will see high temperatures in the
upper 70s to lower 80s. Some locations away from the water may
see mid to upper 80s.

On Thursday the area will continue to see a threat of thunderstorms
along the coast mountains. There is a potential of them moving
over the coast range to affect the inner channels from the very
warm temperatures, elevated mix layer and good energy to keep
them together as them move across the mountains. Later shifts will
need to keep a eye on the meso-scale features.


.HYDROLOGY...With the near record temperatures in the forecast for
the next few days there will be large rises on snow/glacier melt
river systems. A hydrologic outlook was issued for the Taiya River
basin as they may get to minor flood stage by Friday evening and
then again on Saturday evening. Minor flooding will affect lower
portions of the Chilkoot trail.

&&

.LONG TERM.../ Friday to Wednesday as of 10 pm Tuesday / Dominant
ridge over the central gulf extending northward into the central
portion of the state persist from the middle of the week towards
the weekend. A thermal trough of lower pressure is developing
along and over the Southeast Alaska panhandle. It is this blocking
pattern that has allowed warm air to settle into the panhandle
area during the weekend with some well above average temperatures
70s to around 80 degrees lingering into Friday, then cooling
slightly headed into Saturday.

The ridge is starting to break down Friday night into Saturday
leaving a much weaker ridge over the western gulf. The flow along
the central gulf coast and into the panhandle from Saturday into
next week will be reacting different with not as much strong
northwest to northerly flow. With the flattening of the ridge
by Sunday will allow some more moisture, perhaps mainly in the
way of marine layer clouds into the Panhandle. Thus expect a
general cooling trend with more cloud cover and more coverage of
afternoon showers as we head into early next week.

Overall the pattern with new model solutions were not that
different from the current forecast package so only minor changes
were done to the forecast going into the weekend. The main one was
to give temperatures another slight nudge upwards. The forecast
for Tuesday - Wednesday of next week got some minor work for the
winds and pressures to try and align a little better with WPC
solutions for that time frame. No significant weather systems are
expected through the next week.

&&


.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ022.

&&

$$

ABJ/BMB

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