The record
Everything the slot carries, as measured. Series arrays are drawn above and listed here in full.
| event_type | Avalanche |
|---|---|
| ncei_event_id | 728,258 |
| episode_id | 121,289 |
| begin_utc | 2017-12-30T05:00:00+00:00 |
| end_utc | 2017-12-30T05:30:00+00:00 |
| state | MONTANA |
| cz_type | Z |
| cz_name | BUTTE / BLACKFOOT REGION |
| deaths_direct | 0 |
| deaths_indirect | 0 |
| injuries_direct | 0 |
| injuries_indirect | 0 |
| damage_property | 5.00K |
| damage_crops | 0.00K |
| wfo_source | Department of Highways |
| episode_narrative | This was a classic overrunning event with an arctic air mass in place which lasted several days. A push of subtropical moisture associated with an atmospheric river arrived early Friday morning of the 29th and caused a prolonged period of moderate to heavy snow across portions of northwest and west-central Montana and central Idaho. Freezing rain was reported as far north as Polson, east of Thompson Falls, the Bitterroot and Missoula Valleys and in the Seeley/Swan Valley for a period. Between Missoula and Stevensville the precipitation type changed back and forth between snow and freezing rain Friday evening and night. Severe driving conditions were reported all across western Montana on the 29th due to icy roads and blowing and drifting snow. |
| event_narrative | The avalanche moved across Highway 200 for approximately 40 yards in length near mile-marker 55.9 and was 15 to 20 feet deep and 55 yards wide. The cab of a semi-trailer truck was partially buried. Highway 200 was closed until 530 am MST the next morning. Most likely heavy snow and strong easterly winds created severe wind-loading on Mineral Hill contributing to the conditions of the avalanche. According to the Montana Department of Transportation an avalanche of this magnitude had not occurred in this location in over 20 years. |
| year | 2,017 |
Provenance
This slot's source list is not carried on the manifest row; open the dossier below.
Storage: spine