Another push of arctic air came back over the Continental Divide the evening of the 4th, reaching Kalispell during the morning commute on the 5th. S.
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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.
Another push of arctic air came back over the Continental Divide the evening of the 4th, reaching Kalispell during the morning commute on the 5th. Winds were not as strong along U.S. Highway 2 as the previous day but were stronger in Kalispell.
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 4, 3:50 AM MST, 11 hours 10 minutes earlier.
Area Forecast Discussion
National Weather Service Missoula MT
350 AM MST Sun Feb 4 2018
.DISCUSSION...The arctic airmass continues to make its westward
push into the Northern Rockies this morning. Currently, the
arctic has infiltrated the Flathead valley and moved southward to
Polson. The cold air continues to pour over Rogers and MacDonald
passes, as well as through the Highway 12 and 200 corridors.
Conditions have improved significantly overnight in the Glacier
Park and Flathead valley locations, so the warnings have been
allowed to expire or were downgraded. The arctic front is
continuing to cause significant issues around the Garrison
Junction area, so the Winter Storm Warning continues for that
region this morning.
A secondary push of moisture will make its way through the
Northern Rockies later today and tonight from the northwest. This
system will bring widespread precipitation to the region. The
arctic air is anticipated to retreat back to the east this
afternoon, but Glacier Park should still remain under the
influence of this colder airmass. The remainder of the Northern
Rockies will experience relatively high snow levels during this
disturbance so most valleys will receive rain, with snow being
confined to the higher terrain roughly above 5500 feet. Idaho and
Clearwater counties are still anticipated to receive the heaviest
precipitation amounts, potentially creating hydrological
concerns. As for snow amounts: the Glacier Park region will
experience a hefty amount of snow, with West Glacier potentially
receiving 4-6 inches of new snow and higher amounts at Marias
Pass.
After the passage of this disturbance by Monday morning,
arctic air could make another push to the west. In doing so, hazardous
driving conditions could become a concern for the Monday morning
commute, especially for areas that received rain on Sunday
afternoon and evening. Flash freezing could occur and thus, cause
black ice to become rather widespread. We'll keep an eye on this
in the next day or so and assess further.
A period of brief drying will occur Tuesday into Wednesday as the
bulk of precipitation diminishes in valleys across central Idaho
and western Montana. Mountain snow showers could persist during
this time, since the region will remain under unsettled
northwesterly flow. Impacts appear minimal at this time during
this forecast period.
The next organized wintry system looks to begin Thursday and
continue through the day Friday. There are a lot of questions
between forecast models regarding this time frame as to where the
snow levels will end up and how much cold arctic air will (once
again) impact the region in conjunction with the moisture. For
now, plan on a wet Thursday with temperatures dropping into Friday
with snow likely.
&&
.AVIATION...Arctic air has moved into the Northern Rockies overnight.
As a result, KGPI continues to experience gusty northeasterly
winds this morning. KMSO winds have switched to the east, but wind
speeds are not anticipated to be that strong. A secondary push of
moisture will make its way into the Northern Rockies by this
afternoon and overnight, bringing additional aviation impacts to
the region. KGPI will start off as snow, causing reduced
visibilities and low ceilings to start, then switch over to a
rain/snow mix by Sunday evening. KMSO should be mainly rain
throughout the period, with a short window this morning of a
rain/snow mix. KBTM will be switching between snow and rain
throughout the next 24 hours. KSMN will experience showers
throughout the day, but the best chance for precipitation will be
this evening and overnight.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Winter Storm Warning until noon MST today Butte/Blackfoot Region.
Winter Weather Advisory until noon MST today West Glacier Region.
Winter Weather Advisory until noon MST today Potomac/Seeley Lake
Region.
ID...None.
&&The national radar mosaic for the moment the first event began.
2 winter storm, 1 avalanche. Local standard time, as filed.
Severe driving conditions occurred on U.S. Highway 2 from late on the 4th to early on the 5th due to a combination of freezing rain, heavy snow, blowing snow, and icy roads. Snow amounts of 4 to 8 inches were common with wind gusts to 35 miles per hour.
A snow slide occurred across State Highway 1 at mile marker 27.5 near Georgetown Lake early on the morning of the 5th. The northbound lane was impassable with up to 15 inches of snow on the southbound lane.
Snow and blowing snow on the morning of the 5th caused poor driving conditions and numerous accidents during the morning rush hour. The peak wind gust of 39 mph at Glacier Park International Airport occurred at 8:01 am.
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: 733055, 732639, 732638.