Area Forecast Discussion
Issued by NWS Juneau, AK

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

000
FXAK67 PAJK 242255
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
255 PM AKDT Wed Apr 24 2024

.SHORT TERM.../ through Thursday night / A low over central
British Columbia is rotating bands of the showers westward to the
border mountain range and into southern and central panhandle. PoP
levels for showers diminish to 20-30 percent by Thursday morning,
then dry starting Thursday night.

A weak ridge of high pressure over the eastern gulf and western
Canada has holding the weather at bay for most of the area for a
couple of days, and will continue to the start of the weekend.
Winds through the panhandle should be 15 kt or less, daytime
seabreezes are possible which means winds may be flip flopping
direction. Morning fog develop is likely as well from Yakutat,
Cross Sound and western Prince of Wales Island.

.LONG TERM...
Through the long term a Rossby wave will shift towards the
western seaboard carrying an open 500mb trough and associated
surface low into the Gulf. While Friday still looks quite
agreeable, light winds and warm temperatures, expect southeasterly
winds to increase 22-27 knots south of Cape Fairweather into
Dixon Saturday morning along with a southerly 8 to 12ft fresh
swell. The highest of these significant heights look to remain
south of Cape Decision. For this weekend, main areas of concern
for mariners operating in smaller vessels in our waters is Cross
Sound south along the coast of Prince of Wales, southern Chatham,
and southern Clarence into Dixon Entrance.

While the overall theme remains the same for this system,
clusters are starting to highlight an eastward shift of the
surface low over the weekend, with a slightly steeper pressure
gradient stretching into Haida Gwaii. These features in the
ensembles could increase southerly winds west of Haida Gwaii and
in Hecate Strait, resulting in an increase of the significant wave
heights moving into Dixon and southern Clarence; have adjusted
the forecast accordingly.

Regarding precipitation and guidance analysis, we can take two
stances; one of the realistic optimist, while the other is the
defensive pessimist. Regarding the former, guidance from CW3E
Scripps highlights an uptick of IVT moving into Queen Charlotte
sound, with members starting to bring more moisture north into the
southern Panhandle. While amounts and rates still look abysmal,
we could see a bit more rain than our previous forecasts, perhaps
1 to 1.5 inches or so of light rain accumulation through the
weekend into Tuesday morning.

Switching to the defensive pessimist, while a few members of IVT
guidance are bringing rain north, the majority of solutions
continue to keep higher IVT values further south, with less than 1
inch of total rainfall more likely into Monday. To put this
pessimism into context, precipitation sites in the south are
reporting 2 to 4 inches of rainfall over the month, where April
normals for Ketchikan are around 10 inches. For now, the published
forecast indicates less than 1 inch totals over the weekend. No
matter our attitudes on how this metaphorical milk is spilled, the
central and southern Panhandle will likely finish the month far
under normal precip amounts.

&&

.AVIATION...Widespread VFR conditions for the northern panhandle
through the day Wednesday. Southern half of the panhandle will
continue to see lingering showers and associated lower ceilings
through Wednesday night before beginning to thin out a bit. Areas
with thinning cloud cover overnight however are likely to see
another batch of fog, such as on Prince of Wales and also up north
at Yakutat. Similar to Wednesday, these lower conditions in the
morning should quickly give way to VFR conditions by mid to late
Thursday morning. No significant wind concerns.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.

&&

$$

SHORT TERM...Bezenek
LONG TERM....AP
AVIATION...STJ

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.