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000
FXAK67 PAJK 261439
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
639 AM AKDT Sat May 26 2018

.SHORT TERM.../Saturday through Sunday Night/...The water vapor
image this morning shows a broad upper level trough drifting over
the Aleutian Islands with a 135 kt jet streaking NE-ward toward
the Dixon Entrance. This will continue to support the surface low
pressure as it lifts a gale force front northward across SE Alaska
today. The low center will continue to spin as it moves into the
central Gulf Sunday and weaken as it drifts SE towards the outer
coast Sunday night.

What this means for the weekend is rain, and lots of it on
Saturday. Strong winds will also be a concern beginning this
morning along the outer coast from Sitka down south, and by
afternoon move into the Ketchikan/Metlakatla area. Sunday rain
will continue, especially across the southern panhandle and the
outer coast. Yakutat will likely be the dry spot during this
period.

Continued to prefer the GFS solution for this weekend`s weather
event. Considered blending the GFS with the Canadian model, but
the thought was that the Canadian was bringing in a wave that
might be too strong Sunday night across the southern panhandle.


.LONG TERM.../Monday through Saturday as of 10 PM Friday/
Memorial Day continues to contain a wet outlook. The same surface
low pressure that will impact the Panhandle through the weekend
will still be present on Memorial Day over the eastern Gulf. Exact
position remains somewhat uncertain; however, a wet start to the
day is likely across the Panhandle (with the exception of
Yakutat). The surface low looks to slowly weaken and track
southeast through the day allowing showers to diminish from north
to south. While it is unlikely that the evening will be dry up
north, shower activity should be less widespread which may allow
some brief periods of outdoor activity. The southern Panhandle
will struggle to dry out on Monday. On a positive note the
strongest winds will have passed by Monday with only about 10 to
15 knots of wind expected over the inner channels.

The remaining showers will diminish through Tuesday. Then a
surface ridge of high pressure builds behind the low keeping
conditions dry in the middle of the week. This could allow
temperatures to warm depending on the length of the dry period.
Late in the week another surface low pressure system develops;
however, the track and timing of this system is too uncertain to
place in the forecast currently.

The biggest change to the extended forecast surrounded Memorial
Day. The surface low pressure that affects the Panhandle through
the short term was allowed to persist offshore through Monday. The
track of the system was continued from the short term using a
combination of the GFS and ECMWF. The outlying model is the 00Z
(May 26th) NAM which keeps the low center stationary offshore of
Yakobi Island and allows it to weaken in place through Monday.
After Memorial Day newest guidance from WPC did not differ
significantly from the existing forecast so little change was
made.

&&

.AVIATION...Generally MVMC with some pockets of IMC due to both
low CIGS and VSBY for the next 24 hours. Conditions may vary
rapidly over time and space and this has been the case overnight.
Some fog has been observed over the northeast gulf coast
overnight where precipitation has ceased. Am forecasting a break
in the rain tonight over the southern panhandle, so there will be
a good chance for fog showing up over the southern zones late
tonight. Low level jet to 55 kts will result in some LLWS and
turbulence below ridge tops through the day today, then
diminishing overnight. Overall, not a very nice day to go flying
unless you have to.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...Strong Wind until 4 PM AKDT this afternoon for AKZ027.
     Strong Wind from 1 PM to 4 PM AKDT this afternoon for AKZ023.
     Strong Wind from 1 PM AKDT this afternoon through this afternoon
     for AKZ028.
MARINE...Gale Warning for PKZ036-041>043-051.
     Small Craft Advisory for PKZ021-022-032>035-052.

&&

$$

DDH/Fritsch/JB

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