Two relatively mild and moist upper level waves dropped out of Canada, and brought snow and slick roads to north-central Idaho. When the snow started, temperatures ranged from sub-zero single digits, to above zero single digits Fahrenheit.
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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 MSO wrote it up.
Two relatively mild and moist upper level waves dropped out of Canada, and brought snow and slick roads to north-central Idaho. When the snow started, temperatures ranged from sub-zero single digits, to above zero single digits Fahrenheit. Road chemicals were not able to mitigate road conditions at these temperatures, therefore resulting in very slick road conditions until temperatures were able to warm into the 20's to near freezing later on Dec. 10.
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 Missoula, MT wrote its last area forecast discussion before the first event at Dec 8, 1:42 PM PST, 12 hours 18 minutes earlier.
Area Forecast Discussion
National Weather Service Missoula MT
242 PM MST Sun Dec 8 2013
.DISCUSSION...A weak weather disturbance will continue to produce
light snow across the region through the evening but will
gradually taper off. Snow will mainly be confined to areas south
of Missoula in north central Idaho and southwest Montana.
Accumulations will continue to be quite light and thus widespread
impacts to roadways are not expected. Another night of very cold,
subzero temperatures is expected tonight. A brief period of
clearing combined with the fact that cloud cover and light snow
today kept temperatures quite low should allow them to plummet
once more, though not quite a low as the last couple of nights.
A series of weather disturbances will continue to move through
northerly flow aloft through early this week. The next such
feature is due to arrive into northwest Montana early tomorrow
morning. Temperature profiles in the atmosphere will become more
favorable for accumulating snow tomorrow and thus a snow advisory
has been issued for this next wave, mainly across northwest
Montana where roads could become slick for the morning commute
tomorrow. North central Idaho and the rest of western Montana will
likely see snow as well however accumulations are not as certain
and thus have held off on a snow advisory for the time being.
Another similar wave is expected Monday night into Tuesday
morning. Winds begin to increase aloft however, which may begin to
cause downsloping effects and limit valley accumulations slightly.
Temperatures will begin to moderate slightly over the next several
days, however they will still be running well below normal for
this time of year.
Wednesday through Thursday...The models are indicating a low
amplitude ridge of high pressure moving through region. This ridge
should cause a slight warming trend for the Northern Rockies. How
much of warming trend is uncertain at this time. Typically under
a ridge of high pressure valleys develop temperatures inversions.
During this ridge the models are indicating a weak pressure
gradient which should hinder the inversion development. As for
precipitation, the moisture appears to be pushed into northwest
Montana and north of the Canadian border. So at this time, the
chance for precipitation has been trended downward.
Friday on into the weekend, the models are showing a series of
weak disturbances moving through the area from the west. These
features should cause widespread precipitation with the mountains
potentially receiving a significant amount of snow, but amounts
are uncertain at this time. These features appear to be associated
with steady warming of the airmass, which might cause valley
temperatures to climb above freezing.
&&
.AVIATION...A weather disturbance in northerly flow will continue
to produce widespread light snow showers and low ceilings across
north central Idaho and southwest Montana this afternoon. Airfields
KBTM, KMSO and KSMN will be most affected, however conditions
should begin to improve after 09/0000z as drier air moves in
aloft. This will be short lived however as another similar
disturbance moves into northwest Montana early tomorrow morning.
KGPI will be the first to see lowering ceilings and visibility due
to snow, likely around 09/0900z.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY from 3 AM to Noon MST Monday
Kootenai/Cabinet Region...Lower Clark Fork Region.
WINTER WEATHER ADVISORY from 3 AM to Noon MST Monday
Flathead/Mission Valleys...Potomac/Seeley Lake Region...
West Glacier Region.
ID...None.
&&
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https://www.twitter.com/NWSMissoulaThe national radar mosaic for the moment the first event began.
3 winter weather. Local standard time, as filed.
A trained spotter located 3 miles northeast of Orofino, measured 6.0 of total storm snowfall. Four inches of that fell on Monday, Dec. 9. The Grangeville COOP reported 1 of snow with 0.09 of liquid on Dec. 9.
The Pierce COOP measured a total storm snowfall of 4.8 with 0.10 of liquid equivalent. The Dworshak Fish Hatchery measured 3.5 of snow with 0.12 of liquid. Temperatures started off in the negative single digits and rose to near 20 degrees by the end of the event.
The Dixie COOP measured a total storm snowfall of 3.0 with 0.17 of liquid. The Fenn Ranger Station COOP reported 3 of snowfall. The Lolo Pass SNOTEL measured 12 of snow with 0.50 of liquid.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2013Every state in 2013This day in weather historyWarnings in Idaho, December 2013
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: 495695, 495693, 495694.