Montana, 2024

Ice Storm and Winter Weather in Montana, December 7 to 8, 2024

December 7 to 8, 2024 · NWS MSO · 2 events in 2 counties and zones

An atmospheric river brought freezing rain as valleys remained under inversions.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

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.

What happened

The episode as NWS MSO wrote it up.

An atmospheric river brought freezing rain as valleys remained under inversions.

What forecasters said that day

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 6, 2:45 PM MST, 19 hours 30 minutes earlier.

Area forecast discussion, Dec 6, 2:45 PM MST, 19 hours 30 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 ice storm, 1 winter weather. Local standard time, as filed.

Ice Storm, Kootenai/Cabinet Region

When
December 7, 10:15 AM MST to December 8, 6:00 AM MST
Where
Kootenai/Cabinet Region forecast zone
Reported by
Department of Highways
Coordinates
48.171, -114.863 (the zone’s center; the record gives no point)

Up to a quarter inch of ice accretion for many valleys of Lincoln County, including the towns of Libby and Troy. Untreated roads and sidewalks were very icy with many slide offs reported. Side roads were the worst but even primary highways had periods of ice cover. There were reports that some people avoided travel because of the conditions. There was also a power outage in Libby that was related to the weather event.

Winter Weather, Lower Clark Fork Region

When
December 7, 1:30 PM MST to December 8, 8:00 AM MST
Where
Lower Clark Fork Region forecast zone
Reported by
Social Media
Coordinates
47.286, -114.685 (the zone’s center; the record gives no point)

There were several reports of icy roads and sidewalks, especially between Trout Creek and Thompson Falls.

What these are

Ice Storm
Freezing rain accumulating a quarter inch or more of ice, or less where it caused significant damage.
Winter Weather
Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Montana in 2024Every state in 2024This day in weather historyWarnings in Montana, December 2024

Sources

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 2026-10-01. Each event’s entry at NCEI: 1224723, 1222073.