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FXAK67 PAJK 142329
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
329 PM AKDT Sun Jul 14 2024

.SHORT TERM...The heavy rainfall seen over the northern
panhandle and outer coast will continue Sunday night and into Monday
morning as the plume of moisture remains anchored between a ridge in
the southern panhandle and the stalled frontal boundary along off
the coast of the panhandle. This boundary will finally push inland
overnight Sunday into Monday. For more in depth information on
current flood products out for the northern panhandle and expected
impacts from precipitation, see the hydrology section. As the
front pushes inland, the surface ridge over the southern inner
channels will continue to be pinched up against the coast
mountains and winds along the outer coast and inner channels will
increase once more. Southern inner channels will see a bump in
winds from the south as the front finally pushes through the
panhandle Monday.

Winds will be gusty across the panhandle as the front pushes
inland Monday before finally beginning to slacken Monday night.
With the continued southerly flow through the short term
timeframe being offset by precipitation, temperatures will
continue to remain seasonably cool.

.LONG TERM.../Tuesday through Sunday/...
After the previous heavy rain event for the start of the week SE AK
weather while active will not be as impactful. The 500 mb low over
the AK interior remains the driving force for this weeks rain fall.
through the week the center drops southward over the AK Gulf with
lobes extending and continuing to rotate around it. By the next
weekend models have some alignment on the 500 mb pattern, just not
where any of the features will actually be. Tuesday at the surface
ridging over the Eastern Gulf and an open wave trough over the NE
Gulf will keep onshore flow and showers over much of the region.
Tuesday into Wednesday a series of surface waves track up the lee
side of the ridge from the N Pacific bringing shots of increased
precip with highest amounts over the south. Late in the week
tracking the next low moving in. As of now the GFS/Canadian track
should follow the previous surface waves but having a more
solidified structure but the timing difference between these models
is almost 24 hours. Latest ECMWF doesn`t even show a closed low
moving in. GESF ensembles have a closed low but not a deep with low
probability of 6 hour precip exceeding 0.25 inches. ECMWF ensembles
are similar to operational, not much of a feature depicted.

&&

.AVIATION...Weather conditions for southeast AK are a mixed bag this
afternoon with ongoing MVFR/IFR while pockets of VFR and LIFR
conditions are being reported. These conditions are expected to
continue through the evening and overnight periods as ongoing rain
provides lowered CIGs and VIS. Along with the lowered weather
conditions, AAWU guidance through the evening continues to show
turbulence and icing for the northern panhandle with icing extending
farther south to near the southern panhandle. LLWS reports have also
been coming in throughout the day. This is expected to diminish
during the overnight hours but should pick back up again during the
daytime hours, especially along the outer coast of Baranof Island.

&&

.MARINE...For coastal waters, the front has slowed considerably,
with the gradient weakening slightly along the northern coast.
While no longer seeing gale force winds, seas will remain elevated
before subsiding overnight Sunday into Monday morning. For the
southern outer coast, winds will pick up due to the approaching
front displacing the ridge over the area. Coastal waters will see
winds reaching 25 kt with gusts up to 35 kt, with similar
conditions expected for Clarence Strait as the front progresses.
By Monday night the front will have pushed through the panhandle
and winds and seas will begin to subside from north to south.

&&

.HYDROLOGY...Rain continues for the northern panhandle with the
heaviest rain expected this evening and into tomorrow morning for
the northern panhandle. Most places have recorded between 1 and 6
inches of rain across the panhandle. With that much rain, water
levels across rivers and streams have come up. Smaller streams
across the Mendenhall valley have come up and are near bankfull.
Larger rivers such as the Mendenhall River will see a delayed
response due to the amount of rain falling at higher elevations.
This rain along with the warm temperatures will allow for increased
runoff to reach the river basin but at a more delayed rate. Some
river and stream increases across the Haines and Skagway areas have
been less from the rain impacting the area and instead are from
increased snow and ice melt due to warm temperatures aloft. Rain
across the area is expected to decrease as we head into the day
tomorrow as the atmospheric river shifts farther south. One last
resurgence of rain is expected tomorrow though as a shortwave works
into the area but the rain is expected to continue to spread farther
south.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Flood Watch through Monday evening for AKZ318>321-325.
     Strong Wind until 7 PM AKDT this evening for AKZ318.
MARINE...Small Craft Advisory for PKZ012-013-032-033-036-641>644-651-652-
     661>664-671.

&&

$$

SHORT TERM...STJ
LONG TERM....PRB
AVIATION...SF

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