A weather system swept east off the Gulf of Alaska and into the panhandle. Over-running moisture fell as snow across the northern half of the panhandle, followed by ocean affect snow showers in the post front westerly flow.
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 AJK wrote it up.
A weather system swept east off the Gulf of Alaska and into the panhandle. Over-running moisture fell as snow across the northern half of the panhandle, followed by ocean affect snow showers in the post front westerly flow.
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 Juneau, AK wrote its last area forecast discussion before the first event at Dec 9, 2:59 PM AKST, 1 minute earlier.
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
259 PM AKST Thu Dec 9 2021
.SHORT TERM.../Thursday night through Friday night/...the weather
today has been a little calmer when compared to yesterday. A
brief shortwave moved over the panhandle early in the day and it
dropped a quick couple inches, according to morning reports. We
measured 2 inches here at the office the back of the valley. The
rest of the day had rain showers and snow showers scattered around
the panhandle.
Going forward, another round of winter weather is in store for SE
AK. And as such, Winter Storm Warnings and Advisories have been
issued. An area of low pressure near south-central AK and
associated warm and cold fronts are moving towards the panhandle.
As the warm fronts approaches the area, temps tonight should warm
overnight due to warm air moving in. Shortly after the warm front
clears the area, the cold front will being to track through, so
temps for most of the panhandle will likely fall throughout Friday
and into Friday night.
This back and forth with temperatures will lower confidence on
when snow-to-rain and rain-to-snow transitions will happen,
especially in this area where micro-climate zones can make or
break a forecast. But the overall idea is the potential for at
least a rain/snow mix will make it far enough north so that areas
along the coast and areas along and south of Icy Strait could see
a rain/snow mix or rain between 9PM tonight and 3AM Friday
morning. From 3AM and on, cold air will track north to south,
switching any rain or rain/snow mix back to snow by late Friday.
Heaviest snowfall rates look to happen during the nighttime so
Friday morning commutes would be impacted by the fresh snow. The
rest of Friday should see snow rates diminish as the panhandle
enters into a more showery pattern. Friday night temperatures
will cool till they bottom out in the 20s late Friday night.
.LONG TERM.../Saturday through Tuesday as of 3pm
Thursday/...After the heaviest precipitation moves out Friday,
expect snow showers, much colder temperatures, and outflow winds
to begin in the mid-range.
All locations across the panhandle should change back to snow
late Friday. Snow showers will remain through Sunday morning,
resulting in variable amounts across the panhandle. Areas to
watch for advisory level snow include Sitka, Klawock, Ketchikan,
and surrounding areas. Then a break in the clouds and clear skies
are likely at the start of the week.
As this surface low moves along SE along the coast, a strong
pressure gradients will result in outflow winds, with the
strongest gusts expected in the Northern Lynn region late
Saturday. Gusty conditions may lead to gale warnings in the inner
channels this weekend. Models are leaning towards drying out the
panhandle from north to south starting as early as Saturday in the
Northern Lynn once the outflow winds begin. Widespread dry
conditions are expected by late Sunday and will stick around
through Tuesday.
Temperatures will drop significantly through the weekend. The
forecast anticipates the highest temperature during the mid-term
to occur Friday morning. Once areas reach the high for that day,
expect a consistent decrease in temperatures through the weekend
and into the start of next week. Gusty conditions from the
outflow event will help to keep some locations in the Northern
Lynn warmer than model guidance. Looking at the long-term, the
trend seems to continue for December 13 - 17, the CPC is
indicating that we will likely remain below normal for
temperatures.
Focused changes were made to the mid-range forecast today. This
included continuing the dry trend into Tuesday, because chances of
precipitation move back in late Tuesday night. Spent most of the
time focused on the snow amounts in the southern panhandle.
Warning level snowfall is not likely at this time, but advisory
level from the short-waves off the low pressure sitting the gulf
is likely.
&&
.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory from 6 PM this evening to noon AKST
Friday for AKZ025.
Strong Wind from midnight AKST tonight through late tonight for
AKZ020-023-025.
Winter Storm Warning from 9 PM this evening to 9 PM AKST Friday
for AKZ029.
Winter Storm Warning from 6 PM this evening to noon AKST Friday
for AKZ018-019.
Winter Storm Warning until 9 AM AKST Friday for AKZ017.
Strong Wind from 9 PM this evening to midnight AKST tonight for
AKZ017.
MARINE...Gale Warning for PKZ012-013-031-033-034-036-041-043-051-052-310.
Small Craft Advisory for PKZ011-021-022-032-035-042-053.
&&
GJS/KRT
Visit us at http://www.weather.gov/Juneau4 heavy snow. Local standard time, as filed.
NWS Employee reports 9.8 inches of snow overnight in Yakutat.
Cooperative observer in Haines reported 8 inches of snow overnight.
Cooperative Observer in Hyder reported 13.8 inches of new snowfall.
Over 6.5 inches of snow fell in a three hour period starting at 1600 on December 10th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2021Every state in 2021This day in weather historyWarnings in Alaska, December 2021
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: 1000227, 1000231, 1000245, 1000235.