A 969 mb low moving into Bristol Bay pushed a warm front through Southcentral Alaska. Winds ahead of the warm front increased across the Chugach mountains and along Turnagain Arm.
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 969 mb low moving into Bristol Bay pushed a warm front through Southcentral Alaska. Winds ahead of the warm front increased across the Chugach mountains and along Turnagain Arm. In the Kuskokwim Delta, cold air infiltrating behind the storm raised winds along the coast and created blizzard conditions.
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 Feb 19, 4:59 PM AKST, 6 hours 1 minute earlier.
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
459 PM AKST Wed Feb 19 2020
.ANALYSIS AND UPPER LEVELS...
There is a trough and associated surface low over interior
portions of Southcentral moving northward. Showers are diminishing
over the area as this system continues to weaken and move further
inland. A low centered near the eastern Aleutians is rapidly
moving towards the east-northeast. The leading front with this
system stretches from Kodiak Island southward, with the occlusion
positioned from Kodiak westward to near the Pribilofs. Behind
this low over the central and western Bering a surface ridge is
building in, with a trough at the upper levels. This is producing
north winds and showers in cold advection.
&&
.MODEL DISCUSSION...
The numerical models are in good agreement through Friday afternoon
with the synoptic pattern and timing of various surface features.
There are some differences in precipitation, and some
specific weather features are difficult to predict in this
pattern. Therefore the forecast confidence is near normal.
&&
.AVIATION...
PANC...VFR conditions and light winds will persist through
Thursday morning. LLWS is expected later tonight through Thursday
morning as southeast winds aloft increase and flow at the surface
becomes light northerly. The LLWS will end around noon, and
conditions are expected to drop to MVFR in light snow.
&&
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2...Wed night
through Fri)...
Areas of light snow continue to linger from the Mat-Su Valleys
southeast across the Chugach Mountains to Cordova. This is due to
a trough slowly lifting to the northeast. Behind this initial
system, a second strong frontal system will lift from Kodiak
toward the northern Gulf. This system will bring another round of
strong southeasterly gap winds from Portage Valley through
Turnagain Arm and the Upper Hillside of Anchorage beginning later
this evening. Gusty easterly winds are also expected across the
Matanuska Valley. With colder air settling in tonight, areas of
blowing snow are likely from Portage to Palmer during the onset of
the gusty winds before warmer air begins to work in tomorrow.
Blowing snow is also likely overnight tonight into tomorrow for
Turnagain Pass and Thompson Pass. A widespread area of mixed
wintry precipitation will accompany the front, mainly as snow as
the frontal system runs into the colder air. As the front lifts
to the coast and temperatures rise, the snow will change to rain
along the immediate coast. There may even be a brief rain/snow mix
for Anchorage and Palmer as the southeasterly winds aid in
additional warming with highs jumping into the mid to upper 30s.
The cross-barrier flow with this system, however, will provide
some downsloping along the lee of the Chugach Mountains, limiting
precipitation amounts. By tomorrow night, the upper-level trough
begins to lift toward Southcentral and the flow turns more
southerly aloft. This will not only put an end to the strong
winds, but allow for the areal coverage of light snow to increase
across the Anchorage Bowl north to the Susitna Valley. Both the
frontal and the upper-level trough slow and become nearly
stationary late Thursday night into Friday. This will likely allow
the light snow to linger across much of Southcentral through the
end of the work week. With the exception of the mountains, the
highest snow amounts look to be across the northern half of the
Susitna Valley, where at least another 6 inches of snow could fall
by late Friday. Farther south, 2 to 4 inches of looks to be
possible for the Anchorage Bowl and Matanuska Valley through
Friday.
&&
.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A front will move into Southwest Alaska overnight bringing in
snow and some areas of blowing snow. The most significant snow
and blowing snow should be from around Dillingham North and West
where 3 to 6 inches of snow are expected with winds gusting 20
to 30 mph. This is expected to drop visibility to around 1/2 mile
at times in blowing snow. Snowfall is expected to be lighter
in the Kuskokwim Delta toward Bethel as well as north toward the
Kuskokwim Valley due to the strongest part of the front being over
the Bristol Bay area.
The low associated with this front will move eastward Thursday and
Thursday night bringing northwest flow and colder air into Southwest
Alaska for the remainder of the week.
&&
.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
An elongating low is over the Eastern Aleutians through Alaska
Peninsula today with a sharp contrast in temperatures across it.
The rain which has moved into these regions today will give way to
the colder air overnight which will allow snow showers to move
into the region. This colder air will remain over the Bering Sea
and Aleutians through Friday. The next low that will bring some
warmer air will just start to nose into the Central Aleutians
Saturday.
&&
.MARINE (Days 3 through 5 Sat through Mon)...
Westerly gale force winds are expected on Saturday in the Gulf,
which will weaken on Sunday. A low will move from the western and
central Aleutians on Saturday eastward across the eastern
Aleutians Sunday and into the Gulf on Monday. Gale force winds are
expected with this low. Confidence on the timing of this low is
fairly high.
&&
.LONG TERM FORECAST (Days 4 through 7 Sun through Wed)...
On Sunday morning the pattern will consist of an upper level
trough over Southcentral Alaska extending south into the Gulf of
Alaska, an upper level ridge over the central and eastern Bering
Sea, and an upper low over the Aleutians. The trough over
Southcentral will slowly slide east, moving into Canada Sunday
night. The Bering ridge will then build over southern Alaska
Sunday night, sliding slowly eastward through Wednesday when the
axis should be in northwest Canada. The Aleutian low will move
east and a bit north through Wednesday, undercutting the ridge
over southern Alaska.
&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NPW 101. WSW 161.
MARINE...Storm 119 125. Gales 120 130-132 138 150 155 160 165 172-176 180
351 352 413 414.
FIRE WEATHER...NONE.
&&
SYNOPSIS AND MODEL DISCUSSION...BL
SOUTHCENTRAL ALASKA...TM
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...EZ
MARINE/LONG TERM...BL1 high wind, 1 blizzard. Local standard time, as filed.
McHugh Creek reported 24 hours of high winds, with a peak gusts of 86 mph.
Toksook Bay reported 7 hours of low visiblity due to blowing snow. Blizzard conditions were also reported at Chevak and Hooper Bay.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2020Every state in 2020This day in weather historyWarnings in Alaska, February 2020
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: 879433, 879432.