A stalled low pressure system off the coast, in the Northern Gulf, provided an optimal pressure gradient for gusty offshore flow, as it paired with high pressure center over the mainland, and a highly amplified jet stream. The combination of these factors brought high winds through Thompson Pass, and into portions of Valdez, Friday evening, March 3 through late Saturday morning March 4.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS AFC wrote it up.
A stalled low pressure system off the coast, in the Northern Gulf, provided an optimal pressure gradient for gusty offshore flow, as it paired with high pressure center over the mainland, and a highly amplified jet stream. The combination of these factors brought high winds through Thompson Pass, and into portions of Valdez, Friday evening, March 3 through late Saturday morning March 4. Gusts to 75 mph paired with transportable snow for heavy drifting noted near the Thompson Pass gap and blowing snow reducing visibilities down to a mile.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Anchorage, AK wrote its last area forecast discussion before the first event at Mar 3, 5:23 AM AKST, 10 hours 34 minutes earlier.
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
523 AM AKST Fri Mar 3 2023
.ANALYSIS AND UPPER LEVELS...
Most of southcentral and southwest Alaska were relatively quiet
overnight with low pressure systems generally not over land. One
low was over the northern Gulf, another near South Kamchatka, and
a third over the North Pac south of the western Aleutians. Mid-
level high pressure was oriented southeast to northwest toward the
central and western Aleutians. Strong northwest flow was occurring
on the right/north side of the ridge, with a +150kt upper level jet
streak over the Bering pushing onto western AK. At the surface,
strong gap winds with areas of freezing spray were occurring
across the eastern Bering and along the central and eastern
Aleutians to the eastern side of the AKPen.
&&
.MODEL DISCUSSION...
Models are largely in agreement through the weekend. Low pressure
in the Gulf will quickly move southeast out of the area, Low
pressure over the eastern interior will gradually be replaced, and
low pressure near Kamchatka moving northeastward will gradually be
overcome by a faster moving Storm force low moving north out of
the North Pac. Between the low in the Gulf and the approaching
lows from the west, a sharpening ridge will develop. This will
lead to strong warm, southerly flow over the central Aleutians
across the Bering toward Southwest AK.
&&
.AVIATION...
PANC...VFR conditions will continue through the TAF period. Winds
will be northerly at 8-10 kts. Gusts to around 20 kts are possible
in the afternoon.
&&
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
Today through Sunday)...
Dry conditions and mild winds are noted across Southcentral this
morning as the region remains between a weak low located over the
northeast Gulf and a ridge of high pressure moving in from the
west. The stalled low over the northeast Gulf is finally beginning
to move southeastward and will depart the Gulf entirely through
tonight. Meanwhile, a polar airmass continues to infiltrate
Southwest Alaska with 850 mb temperatures ranging from minus 20 to
minus 25 degrees Celsius. This airmass will slide eastward into
Southcentral through tonight with the Western Alaska Range helping
to shunt the brunt of the colder temperatures into the Copper
River Basin. Continued clearing today and tonight will help
produce Saturday morning low temperatures below zero for all but
Prince William Sound. The Copper River Basin will see the coldest
tempeartures with overnight lows in the minus teens and Paxson
could break minus 20 degrees.
A High Wind Watch remains in effect for Thompson Pass and Valdez
tonight through Saturday morning. The typical outflow winds
associated with strong cold air advection are expected to move
into Northeast Prince William Sound tonight. The potential will
exist for gusts to as high as 75 mph early Saturday morning.
However, some uncertainty remains to the extent of cold air
advection through the region, a potential limiting factor for
higher wind gusts. This will be addressed with the afternoon
package as details become more clear.
High pressure will overspread southcentral by Sunday. Conditions
region-wide are expected to improve considerably with a dryspell
to linger into the following week. The one caveat will be the
potential for efficient radiational cooling at night, leading to
colder temperatures in the coming days.
&&
.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3: Today
through Sunday Night)...
Relatively quiet and benign weather will continue to rule the
roost over mainland Southwest Alaska during the short-term period.
The Kuskokwim Delta may get clipped by a system moving north late
this evening into the overnight hours; any precipitation is
expected to be light. Northwest flow through the bays and passes
of the southern Alaska Peninsula will also begin to diminish this
evening into the overnight hours as a ridge builds northward.
The bigger weather story will be the warming trend that Southwest
will experience as the aforementioned tall ridge builds in from
the North Pacific and amplifies over the interior of the state.
Temperatures will rise into the middle 20s for Bristol Bay and the
Kuskokwim Delta by Saturday, and the middle to even upper 30s by
Sunday, as this ridge promotes deep southerly flow across
Southwest. The next forecast package will likely highlight this
trend further.
&&
.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3: Today through
Sunday Night)...
Active weather looks to continue over the Bering Sea and Aleutians
through the short-term period. A ridge of high pressure continues
to build northward over the area today. In response, southerly
flow ensues and warmer temperatures are drawn northward. The
pressure gradient between the northward propagating ridge and
low pressure near Kamchatka will cause a swath of gale-force winds
from the western Aleutians/Bering extending to the central Bering
through this evening. The Kamchatka low's front will continue to
push across the central Bering today while clipping the Pribilof
Islands; precipitation is expected to be light.
Meanwhile, as the amplifying and building ridge continues to
orient itself more northward, a North Pacific low will send its
front northward to the central Aleutian Chain starting this
evening. The low will then move over the central Chain Saturday
morning. Moderate with pockets of heavy precipitation, along with
southeasterly gale-force winds will be common over the central and
eastern Chain as this low continues northward toward Siberia and
the Bering Strait by Sunday morning. The dominant precipitation-
type is expected to be rain due to the warmer temperatures brought
on by deep southerly flow. However, the western Aleutians and
portions of the western Bering could see some snow or rain/snow
mix Saturday evening through Sunday as cold air wraps in on the
backside of the departing low. Another North Pacific low looks to
approach the central and eastern Aleutians Sunday night, but
details on this one are fuzzy at best and will need to be ironed
out as it gets closer in time.
&&
.LONG TERM FORECAST (Days 4 through 7: Monday through Thursday)
The latest model guidance are in good agreement with an anomalous
ridge of high pressure extending northward through mainland
Alaska. Mostly dry conditions are expected across Southcentral
with temperatures above normal through the middle of next week.
Out west, a series of low pressure systems tracks south to north,
bringing southerly winds, warm air and precipitation across the
Aleutians and west coast. There is a quite a bit of uncertainty
with the highly amplified pattern breaking down by midweek. The
GFS has the the ridge axis shifting eastward, but the Canadian/EC
maintain the ridge over the interior state.
&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...High Wind Watch 131.
MARINE...Heavy Freezing Spray Warning 121, 126-130, 136-139, 141,
150, 160, 165, 180, 185, 414.
Gale Warning 120-121, 126-127, 130-132, 136-138, 150,
165, 170, 172-178, 180-181, 185, 351-352, 411-414.
FIRE WEATHER...NONE.
&&
SYNOPSIS AND MODEL DISCUSSION...NR
SOUTHCENTRAL ALASKA...BL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DN
LONG TERM...MFSPECIAL WEATHER STATEMENT National Weather Service ANCHORAGE AK 330 PM AKST Fri Mar 3 2023 AKZ152-155-161-041400- Lower Kuskokwim Valley-Kuskokwim Delta-Bristol Bay- Including the cities of Aniak, Sleetmute, Bethel, Nunivak Island, King Salmon, Dillingham, Naknek, and Pilot Point 330 PM AKST Fri Mar 3 2023 ...ABOVE FREEZING TEMPERATURES FOR SOUTHWEST ALASKA THIS WEEKEND THROUGH EARLY NEXT WEEK... A series of low pressure systems will bring warm and windy conditions to the area Saturday through Monday. The first low pressure system will increase temperatures to the 20s and 30s with Sunday and Monday continuing to warm in the 30s and 40s. The Kuskokwim Delta will see the warmest conditions with highs in the lower 40s on Sunday and Monday. Bristol Bay and the Kuskokwim valley can expect temperatures in the mid to upper 30s. Strong winds are also expected across the Kuskokwim Delta with gusts near 50 mph along coastal locations with the strongest winds expected on Sunday. The rest of the area will experience light winds. These strong winds may cause water to come over the ice along coastal locations.
1 high wind. Local standard time, as filed.
DOT reported that wind gusts reached 75 mph around 2:00 am along with heavy drifting snow in and near the Gap, while visibility reduced to 1 mile.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2023Every state in 2023This day in weather historyWarnings in Alaska, March 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1105179.