Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

000
FXAK67 PAJK 262041 AAA
AFDAJK

Southeast Alaska Forecast Discussion...Updated
National Weather Service Juneau AK
1241 PM AKDT Mon Jun 26 2017

.SHORT TERM.../ Monday to Wednesday / The remains of the old low
from the weekend dissipated and the upper level support is moving
into central British Columbia early Monday. The flow about that
low is drawing a band of colder topped clouds south over the
central panhandle towards the Prince of Wales area. Some lower
clouds over the northeast gulf and along the Icy Strait/Cross
Sound area to Gustavus and likely to Yakutat, though higher clouds
on the satellite imagery is hiding that feature this morning.
Isolated to scattered showers through Monday and Monday night due
to combination of the flow over the coast range into the
panhandle, and a westerly orographic lifting pattern.

Short wave(s) ejecting out of a low over the Bering Sea see still
have Tuesday to Wednesday are trying to lift over the Gulf of
Alaska ridge. Am expecting the best rain fall areas Tuesday into
Wednesday over the north central gulf east to near Cape
Fairweather.

Local pockets of 25 kt winds in the Northwest flow along the
panhandle Monday evening have a few areas of small craft
advisories on Monday night. Over Lynn Canal do expect the
southerly winds to pick back up to 20 to 25 kt range in the late
afternoon and evening as well.


.LONG TERM...Thursday through Monday...As of 930 PM Sun...Period
begins with upper ridge just E of the AOR as an upper trough
approaches the W gulf. Models continue to struggle with this
details regarding the approaching trough and the timing and
strength of short wave troughs ejecting out from the parent
trough. coming to a consensus on the approaching trough. Given the
large model discrepancies, elected to maintain inherited forecast
with precip chances increasing along the N gulf coast Wed then
spreading into the entire panhandle Thu. Timing better precip
chances will improve as systems approach, but for now kept chance
PoPs across most of the CWA with AKZ017 having highest chances
late this week. Model solutions diverge more significantly late
this week into the weekend. EC solution is fastest with a closed
upper low moving across the S gulf/N Pac. GFS/GEM have similar,
but slower solutions with ensemble means favoring the slower
progression of this feature. Since model agreement is poor by the
middle of the week, do not favor any solution for next weekend.
Made minimal change to inherited forecast and kept it trended
towards WPC guidance late this week through weekend.

&&

.AVIATION...As of 1PM/21 UTC Monday...The ridge of high pressure
over the gulf developed a marine layer of low clouds overnight that
has kept majority of the region under MVFR CIGS and down to IFR over
the outer coast including PAYA. Showers linger over the southern
half of the panhandle with low skud clouds hanging around the
mountains. However NWLY flow over the panhandle is making for large
breaks in the clouds on the lee side of Baranof Island along with
gravity waves that could create some turbulent conditions southward
over POW Island. Expect CIGS to lift some more through the early
evening and showers to decrease but likely will not end completely
since moisture will continue to be fed over the top of the ridge.
Overnight the marine layer will strengthen again with MVFR CIGS
likely through the early morning hours of Tuesday.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ012-022-041>043.

&&

$$

Bezenek/Fritsch/BC

Visit us at http://www.weather.gov/Juneau


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.