Arctic air pushed across the Divide and into the Kalispell area on the evening of 14th leading to a period of moderate snow and gusty winds with associated impacts.
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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.
Arctic air pushed across the Divide and into the Kalispell area on the evening of 14th leading to a period of moderate snow and gusty winds with associated impacts.
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 Feb 14, 2:49 PM MST, 3 hours 56 minutes earlier.
Area Forecast Discussion
National Weather Service Missoula MT
249 PM MST Wed Feb 14 2018
...Significant winter storm possible Saturday into Sunday across
western Montana and central Idaho...
.DISCUSSION...Snow continues to spread across the Northern Rockies
this afternoon. However, most roads have become wet with the
afternoon heating. This will change this evening, as a modified
arctic airmass spills over the Continental Divide, bringing a re-
enforcing shot of cold air and another round of snow. This will
initially begin over northwest Montana around sunset. The arctic
boundary will slide south into west-central and southwestern
Montana overnight tonight. Most valley locations along and north
of the I-90 corridor will see an additional 1 to 3 inches of new
snow, with isolated higher amounts by morning. The morning commute
tomorrow is expected to be slick and snowcovered. Due to this, a
number of winter weather advisories remain in place. Further
details can be found by visiting www.weather.gov/Missoula.
The one area that remains up in the air is the Missoula and
Bitterroot Valleys. The locations most likely to be impacted with
accumulating snow overnight will be from Missoula, south to Lolo.
At this time, the arctic boundary doesn't appear to make it much
further south than Lolo, allowing only a trace to one half inch of
snow to accumulate in those areas. North-central Idaho will only
see scattered snow showers overnight. Though, what showers do
develop, could bring a quick burst of moderate snow accumulating
up to an inch or 2 for the higher valleys, such Grangeville and
surrounding areas.
The next weather system will begin to cause snow into the Idaho
Panhandle and northwest Montana early Friday morning, spreading
further south into the rest of western Montana and central Idaho
Friday afternoon and evening. The heaviest snow is expected in the
higher terrain of central Idaho and northwest Montana, including
mountain passes such as Lookout, Lolo and Marias. Moderate to
heavy snow over these passes could make for slow travel at times,
while valleys will see light to moderate snow. Expect slick roads
for most areas. A period of snow banding looks possible late
Friday evening into Saturday morning, which could cause more
focused intense snowfall, but where these bands may set up is
difficult to pinpoint at this time.
A significant weather system will begin to affect the region
Saturday afternoon and lasting into Sunday evening as moist flow
aloft encounters a cold arctic airmass moving over the Continental
Divide at the surface. Moderate to heavy snow, gusty northeast to
east winds, blowing snow causing low visibility and significantly
colder temperatures can all be expected in this time frame. Travel
may become difficult to hazardous due to the combination of these
factors. The most significant impacts will likely be felt in
western Montana, though central Idaho will see potentially
significant snow and much colder temperatures. More details to
follow on this system.
Monday into Tuesday will see a gradual drying in conditions as
much colder and drier air settles over the region. Temperatures
could approach some of the lowest we have see so far this winter
season.
&&
.AVIATION...Scattered snow showers continue to spread across the
Northern Rockies, occasionally lowering ceilings and reducing
visibility. As the evening wears on, an arctic boundary will begin
to impact the region, bringing a re-enforcing shot of cold air,
gusty northeasterly winds, and another round of snow. KGPI will be
impacted first around 15/0200Z with moderate snow and gusty winds
up to 25-30kts through the night. KMSO will see the winds and snow
by 15/0600Z tonight, and continue through mid morning. 2 to 4
inches can be expected for KGPI by morning, with 1 to 2 inches for
KMSO. KBTM will see similar snow amounts and timing as KMSO,
though not expecting the easterly winds.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory until 11 AM MST Thursday
Flathead/Mission Valleys.
Winter Weather Advisory until 11 AM MST Thursday West Glacier
Region.
Winter Weather Advisory until 5 AM MST Thursday Kootenai/Cabinet
Region.
Winter Weather Advisory until 5 AM MST Thursday
Bitterroot/Sapphire Mountains.
Winter Weather Advisory until 11 AM MST Thursday Potomac/Seeley
Lake Region.
Winter Weather Advisory until 11 AM MST Thursday Butte/Blackfoot
Region.
Winter Weather Advisory until 5 AM MST Thursday Lower Clark Fork
Region.
ID...Winter Weather Advisory until 4 AM PST Thursday
Orofino/Grangeville Region.
Winter Weather Advisory until 4 AM PST Thursday ABOVE 4000 FEET
for the Lower Hells Canyon/Salmon River Region.
Winter Weather Advisory until 4 AM PST Thursday Northern
Clearwater Mountains...Southern Clearwater Mountains.
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
629 PM MST WED FEB 14 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0500 PM SNOW 3 NNW CORAM 48.47N 114.07W
02/14/2018 M4.0 INCH FLATHEAD MT TRAINED SPOTTER
THE DURATION OF THE SNOW EVENT WAS 24 HOURS.
&&The national radar mosaic for the moment the first event began.
1 winter storm. Local standard time, as filed.
Severe driving conditions occurred in the Flathead Valley due to a combination of snow, blowing snow, and flash-frozen roads. A peak wind gust of 41 mph was observed at the Glacier Park International Airport, along with 4 inches of new snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2018Every state in 2018This day in weather historyWarnings in Montana, February 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: 732647.