Graphical Hydro Meteorological Discussion

408
FXAK68 PAFC 170032
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
432 PM AKDT Sat May 16 2026

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: This
afternoon through Tuesday afternoon)...

Wet and/or windy for much of Southcentral this weekend as an
unseasonably strong storm system impacts the region. Wind
Advisories are in effect for Anchorage and Lower Mat Valley, and
Special Weather Statements are in effect across Kenai Peninsula
and Prince William Sound. The highest precipitation amounts will
be in Kodiak Island and along the Gulf coast (including Prince
William Sound), with only isolated showers expected for more
interior locations through tomorrow morning. From the latter half
of Sunday through much of Monday, expect rain showers with breezy
afternoon winds. By late Monday, the next low brings widespread
rain as it moves from the North Pacific into Southcentral.

&&


.SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA/ALEUTIANS
(Days 1 through 3)...

A now weakening low pressure system, with a center just southeast
of the Pribilof Islands, continues to define the weather pattern
across Southwest Alaska and the Bering Sea. The low has pushed a
front into the Southwestern Alaska coast, spreading gusty
southeasterly winds and light-to-moderate rainfall rates across
the region. Strongest winds and rainfall is along the mountainous
Alaska Peninsula and Ahklun Mountains. Precipitation associated
with the low pressure center is broad enough to include the Alaska
Peninsula, the eastern Aleutians including
Unalaska/Nikolski/Akutan, and the Pribilof Islands. The
precipitation type across this system is predominantly rainfall,
with only the Pribilof islands seeing snowfall, but no
accumulations on the ground are expected. The Bering low remains
stationary overnight into Sunday late morning allowing for
continued rain showers and breezy conditions. Through Sunday
afternoon and evening, the Bering low continues to broaden and
weaken as it moves west of the Pribilof Islands. A North Pacific
low moves toward the Alaska Peninsula bringing another round of
rain and southerly winds to Southwest Alaska, portions of the
Aleutians and the Alaska Peninsula Monday.

-CL

&&

.LONG TERM FORECAST (Days 4 through 7: Wednesday through
Saturday)...

A broad upper-level trough over the Bering Sea extending into the
Gulf looks to remain in place through at least early to mid next
week. This will support continued unsettled conditions across much
of southern Alaska.

By midweek, focus shifts farther west as the active Bering Sea
pattern continues. Another low is expected to move off Kamchatka,
though model guidance remains split on its track. The
European/Canadian models keep the low a bit farther north of the
Aleutians, while the GFS favors the low just to the south of the
Aleutian Chain. Regardless of the exact track, unsettled
conditions are expected to persist across the Aleutian Chain as
this system and its associated front progress eastward through
Friday.

LM

&&


.AVIATION...

PANC...VFR conditions will prevail through the TAF package.
Strong southeasterly winds will continue through around midnight
as a frontal system approaches. Sustained winds of 15 to 25 mph
with gusts 30 to 45 mph are likely. Winds are expected to quickly
turn northerly and diminish as the southeasterly winds coming out
of Turnagain Arm turn down Cook Inlet through Sunday. This
expected wind shift will likely coincide with a period of
continued gusty southeasterly winds aloft over the Chugach
Mountains, resulting in the potential for LLWS from around
midnight through Sunday morning. South-southeasterly winds are
expected to redevelop by late Sunday morning with gusts of up to
35 mph possible through late Sunday evening. Chances for rain
showers increase late Sunday.

-TM

&&


$$

966
FXAK69 PAFG 171145
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
345 AM AKDT Sun May 17 2026

.SYNOPSIS...
Spring-time is here for areas south of the Brooks Range as the
snow continues to melt, river breakup progresses further
downstream, and temperatures remain steadily in the 50s and 60s
through the weekend. The North Slope, however, is expected to
continue to see temperatures in the upper 20s and lower 30s with
areas of stratus and fog expected to continue into later this
morning. East/northeast wind gusts are expected to increase for
the NW Arctic, possibly resulting in areas of blowing snow and
reduced visibility. A Bering Sea low will bring robust moisture
resulting in scattered precipitation for the West Coast and
Western Interior today. A series of fronts associated with this
low will bring isolated to scattered showers for the Interior
beginning Monday, with the possibility of isolated thunderstorms
to be associated with these showers. Wind Advisories continue for
gusty southerly winds today through the Alaska Range passes and
Delta Junction. Dry conditions and gusty winds for Delta Junction
will lead to Red Flag conditions this afternoon.

&&

.KEY WEATHER MESSAGES...

Central and Eastern Interior...

- Winds remain gusty in the AK Range with Min RH around 20% and
wind gusts over 50 mph in Isabel Pass and Delta Junction
resulting in a Red Flag Warning this afternoon and evening. A
Wind advisory is also in effect through 1 PM this afternoon in
Windy Pass for gusts up to 60 mph.

- Isolated to scattered showers are expected to begin for the
Interior on Monday into Tuesday with the possibility of
isolated thunderstorms to be associated with these showers.

West Coast and Western Interior...

- Isolated showers possible along a front extending from the
Seward Peninsula to Lake Minchumina. A thunderstorm is possible
in the northwestern Seward Peninsula as well (10% chance).

- Isolated to scattered showers in the YK Delta and Lower Yukon
with the next chance for widespread rain coming on Tuesday.

North Slope and Brooks Range..

- Chilly temperatures persist with highs in the 20s and lows in
the teens along the North Slope. A gradient of temperatures
across the Brooks Range with highs in the 50s to near 60 along
the southern slopes and low 40s for the northern slopes.

- Northeast winds are expected to increase tonight and into
tomorrow for the western North Slope, which could result in
areas of blowing snow and reduced visibility.

- Mainly dry conditions are expected for the next few days with a
slight chance for showers and even a thunderstorm in the eastern
Brooks Range on Tuesday.

&&

.FORECAST ANALYSIS AND DISCUSSION...

A Bering Sea low will draw additional moisture northward due to a
series of relatively weak fronts, bringing isolated showers for
the YK Delta and Seward Peninsula today. Accompanying these
showers will be gusty easterly/southerly winds for the YK Delta
and Western Interior. There is also a slight possibility of
freezing rain in the western Seward Peninsula tonight into
tomorrow morning. These winds will generally be strongest in the
afternoon and evenings and could see gusts as high as 35 to 40
mph. A more substantial shortwave will rotate around the low late
Monday into Tuesday, bringing isolated to scattered showers for
the Interior and persist through the week. Isolated thunderstorms
are possible with these showers, especially towards the first half
of the week. This shortwave will likely bring steadier
precipitation for southwest Alaska with the highest amounts
expected in the YK Delta and southwest Interior.

Due to this low remaining in the Bering Sea throughout the
weekend and a Northeastern Arctic High, a pressure gradient will
form over the state, especially over the Alaska Range. Upwards of
6 mb of a pressure gradient and southerly flow through the Alaska
Range will continue to produce gusty winds today, with the
strongest wind gusts as high as 60 mph possible this morning in
Isabel and Windy Pass and 50 mph in Delta Junction. Wind
Advisories have been issued for both areas. As a result of these
strong winds and dry conditions, a Red Flag Warning has been
issued for Delta Junction throughout the rest of the day.

The North Slope is expected to remain chilly through the beginning
part of this week. Northeast/east wind gusts are expected to
increase to as high as 35 mph in the northwest Arctic beginning
tonight and into tomorrow, resulting in the possibility of blowing
snow.

&&

.FIRE WEATHER...

The main fire weather concern continues to be around Delta Junction,
where winds will remain elevated out of the south through Sunday
with afternoon RHs dropping to as low as 20%. Sustained winds will
be around 25 to 35 mph with gusts up to 50 mph in Delta and 60 mph
towards Isabel Pass through at least Sunday afternoon. Winds will
likely remain elevated for much of next week in this corridor, which
are expected to peak on Tuesday and again on Thursday. RHs will
increase tonight and Sunday night but only up to 50% so recovery
will not be great. We will be monitoring for potential red flag
conditions into next week, but for now, a Red Flag Warning is in
effect for Delta Junction through Sunday evening with the most
critical times being Sunday afternoon with marginal recovery
overnight. Otherwise, no significant thunderstorm potential exists
through much of the upcoming week outside of very isolated activity,
with rain showers most abundant in the Western Interior as a series
of fronts move through the area. More organized showers farther west
will shift towards the Central/Eastern Interior midweek, keeping
daily shower chances and clouds around beyond that into next
weekend. Highs across much of the forecast area will be in the 50s
and mid 60s with lows in the 30s/40s through the week ahead, with
afternoon MinRH around 25-40% for the Interior.

&&

.HYDROLOGY...

Yukon River:
No significant changes to the ongoing flood products and river
forecasts. The breakup front on the Yukon is now approaching
Grayling but there is no significant concern for flooding as it
heads there. Water remains high on the Yukon upriver from the
breakup front due to snowmelt with a Flood Warning remaining in
effect in Galena. No significant flooding is expected from this
high water.

Buckland River:
There have not been any updates since yesterday. If any new
information comes out, we will update the flood watch.

Chena:
The Chena River continues to respond to warmer temperatures with
higher elevation snowmelt leading to rivers running higher than
normal, but likely remaining below action stage.

Additional Information:
Visit www.weather.gov/aprfc for the latest hydro information.

Please report observed flooding to local emergency services, law
enforcement, or to the National Weather Service when you can do so
safely.

&&

.EXTENDED FORECAST DAYS 4-7...Wednesday through next Saturday.

No significant changes to the upper level pattern are expected
through extended forecast, which will continue to be dominated by
upper level troughing over Western Alaska and the Bering Sea and
upper level ridging in the NE Pacific. This setup will continue to
support broad southerly flow into Northern Alaska which while
holding temperatures steady, will lead to moisture and associated
cloud cover building into our region. On Wednesday, models remain in
reasonable agreement on a series of two lows: one around 1000 mb in
the Gulf of Alaska and a secondary, stronger low centered near the
Central Aleutians around 975 mb. Moisture from the low in the Gulf
of Alaska and a shortwave trough lifting north between these two
features will help kickoff daily, scattered rain showers with high
elevation snow showers generally above 3000 to 4000 feet.

As that low now in the Bering Sea by Thursday continues to lift
northeast towards our region, we will see an enhanced pressure
gradient develop between this low and high pressure over the High
Arctic. As a result, winds will broadly see an increase Thursday
with strongest winds expected along the West Coast, St. Lawrence,
Delta Junction, and through Alaska Range Passes. These locations are
where we are expecting gusts to be around 30-50 mph, locally
stronger in the Alaska Range up to around 65 mph. While breezy winds
are expected to continue earlier on Wednesday through the Alaska
Range, our best Wind Advisory regime is still looking like Thursday.
Given the time of year with temperatures across much of our region
south of the Brooks Range seeing highs hold steady well into the 50s
and 60s outside of some 30s/40s along the West Coast, daily very
isolated thunderstorms will also be possible that will peak in
coverage each afternoon and evening with a focus on the Interior.

Temperatures won`t be changing too much as highs range from the 50s
to 60s in the Interior and 40s/50s along the West Coast. The North
Slope will be chilly through the middle of next week. As fronts
continue to drift north, it has the chance gradually erode the cold
air which could bring some warmer air into the area by the end of
next week. The main reinforcing driver for the colder temperatures
across the North Slope continues to be high pressure in the High
Arctic, leading to colder and drier conditions and keeping the storm
track across Alaska staying farther south.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory for AKZ837-849.
Flood Watch for AKZ818-829.
Red Flag Warning for AKZ937.
Wind Advisory for AKZ847.
PK...Small Craft Advisory for PKZ801-850.
Small Craft Advisory for PKZ802.
Brisk Wind Advisory for PKZ810.
Small Craft Advisory for PKZ811.
Brisk Wind Advisory for PKZ812.
Small Craft Advisory for PKZ816.
Small Craft Advisory for PKZ817.
Small Craft Advisory for PKZ851-854.
Brisk Wind Advisory for PKZ856.
Brisk Wind Advisory for PKZ857.
&&

$$

Lewis
MacKay - Extended/Fire Weather

756
FXAK67 PAJK 171236
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
436 AM AKDT Sun May 17 2026

.SYNOPSIS...

Key Messages:

- Our break from the rain will come to an end Sunday.

- A gale force front with winds 35 kt to 45 kt moves into the
northeastern Gulf of Alaska Sunday. Gale Warnings are posted for
the open gulf north of 57 degrees north latitude and from Cape
Spencer northwest through Cape Suckling.

&&

.SHORT TERM...A broad low stretching from the NW gulf over to the
Alaska Panhandle will throw a gale force front towards SE AK
Sunday. Upper and mid level clouds are already spreading over the
outer coast and inner channels and will continue to push inland
through the morning hours. These upper level clouds provided just
enough of a cap over SE AK to prevent significant cooling
overnight, contrary to Friday night. This also helped to mitigate
fog formation along the inner channels, with only Ketchikan and
Wrangell managing to report shallow stratus as of this discussion.

Precipitation will not be far behind these higher clouds Sunday
morning, with Yakutat along the northeast coast first in line and
the rest of the panhandle following suit by the early afternoon
hours. No significant changes were made to the precipitation
forecast with light to moderate rain through the day, though not
enough for any significant hydrologic response to cause flooding
issues. The strongest winds are expected to stay offshore out in
the gulf, however coastal communities will see winds pick up and
could have a brief period of gusty winds coinciding with a
southerly wind shift once the front lifts inland. Rain will last
through Sunday before gradually diminishing Monday for the
southern panhandle under the influence of a ridge building in
behind the front. However, the panhandle north of Frederick Sound
will likely continue to see moisture ride over the ridge and
continue to bring showers to start the week.

.LONG TERM.../TUESDAY THROUGH FRIDAY/...Moisture lingering from
Monday`s precipitation looks to stick around the northern
panhandle through the day on Tuesday, bringing cloudy skies and
chances for rain. However, the central and, especially southern
panhandle will see more clearing though the day Tuesday before
another front moves across the area early or mid Wednesday
morning. This will bring more widespread rain to the panhandle,
with higher accumulation totals aimed at the northern panhandle,
mainly Yakutat and Juneau. Rain is anticipated to diminish again
through the day Thursday across the entire panhandle which also
brings the chance for clearing skies going into late next week.
/Perez

&&

.AVIATION.../through Sunday night/...Mainly clear skies overnight
have lead to patchy low stratus development across the southern
panhandle, with bkn-ovc CIGs 5-10kft near PAKT and PAWG, as
evident on local FAA webcams this morning. Otherwise, expect
lowering CIGs as the next front spreads rain from west to east
across SE AK today. Rain will likely lower VIS down to MVFR and
bring down CIGs to MVFR to possibly IFR. Increasing winds through
the afternoon becoming 10-20G20-30kt, with a slight decrease down
to 10kt or less late tonight behind the frontal passage. Winds for
PAGY and PAKT look to stay elevated 10-15G20-25kt through the
night. LLWS increases as well today as winds 2kft aloft becoming
30-40kt.

&&

.MARINE...
Inside (Inner Channels): Most of the inner channel winds
diminished overnight Saturday, with the primary exceptions being
Lynn Canal and Stephens Passage which continue to see 15 to 20 kt
southerly winds as of 4 am Sunday. A strong low with an
associated gale force front is moving northward in the gulf and
will bring widespread SE fresh to strong breezes of 15 to 25 kt
through the day Sunday. Strongest winds will be located over
Cross Sound Sunday afternoon. Winds will then diminish late Sunday
into Monday with the exception of Northern Lynn Canal where winds
are expected to increase once again by Monday afternoon to around
15 to 25 kts as a ridge slides in behind the previous front.

Outside (Gulf and Coastal Waters): A gale force front is advancing
towards the panhandle Sunday, with buoy 46082 already reporting
gusts up to 39 kt as of 430 am. Strongest winds will be located
across the northern to eastern gulf with winds of 35 to 45 kts.
Along with these strong winds, significant seas will build to 15
to 20 ft Sunday morning. Winds and seas will remain elevated
through the day Sunday before before diminishing and once again
becoming southwesterly late tonight and into Monday. Even as gulf
winds greatly diminish, seas will struggle to subside and thus
remain around 8 to 12 ft into Monday.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ644-651-652-664-671-672.
Small Craft Advisory for PKZ022-036-053-641>643-661>663.

&&

$$

SHORT TERM...STJ
LONG TERM...AGP
AVIATION...DS
MARINE...STJ

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