Strong arctic high pressure had built into the Yukon Territory up to 1037 MB on 1/9 and 1/10. Very strong outflow winds were reported in Downtown Haines up to 60 mph causing damage on the afternoon of 1/9.
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.
Strong arctic high pressure had built into the Yukon Territory up to 1037 MB on 1/9 and 1/10. Very strong outflow winds were reported in Downtown Haines up to 60 mph causing damage on the afternoon of 1/9.
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 Jan 9, 10:34 AM AKST, 2 hours 26 minutes earlier.
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1034 AM AKST Tue Jan 9 2018
.UPDATE...Arctic front continues to sag southward very slowly this
morning. Mid level DPVA ahead of the upper trough over the
northern Panhandle will combine with low level frontogenesis to
increase the forcing for ascent along the Gulf coast this
afternoon and evening. Forecast soundings indicate steep lapse
rates atop a sharp low level frontal zone which will enhance the
precip rates with snow showers this evening. Due to the showery
nature of the precip, it is hard to pin down areas that may have
more significant accumulations so went with a winter weather
advisory in the areas where the best forcing is likely to not be
undercut by drying easterly outflow. Think a general 2 to 6 inches
are likely mainly for outer coastal areas from Pelican to Sitka.
Showers will gradually decrease in intensity and coverage late
this evening as the upper trough shears off to the east and the
front continues pushing south.
&&
.PREV DISCUSSION...ISSUED AT 6 AM Tuesday...
SHORT TERM.../Tuesday through Wednesday as of 6 AM Tuesday/ A
windy day with scattered snow showers is in store for the
Panhandle. Tuesday morning begins with a weak low pressure system
over the north central gulf. At the same time shower activity over
the gulf and Panhandle is being enhanced by an upper level trough
with embedded short waves descending over the Panhandle. Shower
activity is expected to diminish from north to south today as
northerly outflow increases.
High pressure over the Yukon with lower pressure south of the
Panhandle has created a favorable pattern for strong northerly
outflow winds. Winds will increase through the day and peak during
the evening hours, slightly later than originally forecast. Strong
winds with gusts to 40 mph are expected near Downtown Juneau and
Douglas as well as Skagway beginning this afternoon and
continuing into the overnight hours. Temperatures will also
decrease as northerly outflow increases with maximum temperatures
tomorrow nearly 10 degrees cooler over the northern Panhandle on
Wednesday. These cooler temperatures coupled with strong winds
will produce freezing spray over the inner channels. While winds
will peak this evening, the outflow pattern persists into
Thursday.
A fair amount of changes were made in the short term
forecast. Winds were decreased over the northern inner channels
and northern Panhandle land areas today and tonight to account for
the weaker outflow pattern. One thing to note is models have been
over estimating the surface pressure gradient, which helped in
decision making with reducing wind speeds. In addition,
temperatures were warmed in areas with downslope wind to account
for enhanced warming. The weaker outflow pattern also lead to an
increase in temperatures as a whole in the short term. Scattered
and isolated snow showers were also added to the forecast through
today. Primary guidance was a blend of the 06Z NAM and 00Z
Canadian models.
LONG TERM.../Thursday through Monday night/ Building upper ridge
over the Western US and Canada along with an increasingly negative
tilting trough over the Bering Sea and NE Pacific will bring
warmer and wetter weather to the panhandle through next weekend.
This overall pattern has not changed much compared to the guidance
from yesterday.
At the surface, forecast remains rather wet with warming
temperatures as overall south flow brings in a series of fronts.
There is a difference between ECMWF/Canadian and GFS/Nam on when
the precip will actually start late this week. ECMWF/Canadian
favor precip starting as early as Thu night for at least the
southern half while GFS/Nam hold off until Fri. Because of this
difference, chance pops remain in the forecast Thurs night into
Fri. First substantial front comes in Fri night into Sat with a
second front coming in Sat night. Temperatures initially appear
cold enough for snow for many areas Fri night but strong warm air
advection will warm quite a few areas up above freezing as early
as Sat afternoon facilitating a change over to rain. Haines and
Skagway will likely remain snow until possibly Sun afternoon if
they warm up that much at all. Precip may start to slacken off
toward late weekend and early next week as some guidance is
suggesting that the upper trough will tilt enough to pull most
systems farther west.
With the active forecast, winds will also be a factor. Outflow
winds in the inner channels will be shutting off, and then
switching to a southerly direction for all but Lynn Canal. Out in
the gulf, Friday and beyond will be mainly characterized by
nearly continuous 25 to 35 kt SE winds as one front after another
moves through. Wave heights will also be on the increase with 20
foot seas possible in the gulf by the weekend.
Few overall changes made compared to the previous forecast.
Temperatures for the weekend and beyond were raised a few degrees
and if guidance continues to show really strong warming may need
to be raised more in future forecasts. Otherwise, main changes
dealt with local effect in the mid range. Used mainly WPC for
updates.
&&
.AJK Watches/Warnings/Advisories...
PUBLIC...Strong Wind through late tonight for AKZ025.
Winter Weather Advisory until 11 PM AKST this evening for AKZ022-
023.
Strong Wind through this evening for AKZ018.
Wind Chill Advisory until 2 PM AKST Wednesday for AKZ018.
Strong Wind until 6 PM AKST this evening for AKZ017.
MARINE...Gale Warning for PKZ011>013-022-031-032-034-043-051-053.
Small Craft Advisory for PKZ021-033-035-042-052.
Small Craft Advisory due to Seas for PKZ041.
&&
DEL/JB/EAL
Visit us at http://www.weather.gov/JuneauPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JUNEAU AK
801 AM AKST TUE JAN 9 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0800 AM SNOW YAKUTAT 59.54N 139.73W
01/09/2018 M5.3 INCH AK OFFICIAL NWS OBS
MEASURED SNOW THAT FELL BETWEEN 3 PM MONDAY AND 8 AM
TUESDAY MORNING.
&&
JWA1 high wind. Local standard time, as filed.
The Marine Exchange observation recorded gusts to 60 MPH for the Haines Harbor (Downtown) on the afternoon of 1/9. Local newspaper reported that a ski rack was torn off a car and went through the window of a downtown business. Other damage was reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2018Every state in 2018This day in weather historyWarnings in Alaska, January 2018
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: 726766.