A favorable weather pattern steered a jet stream across the region. Atmospheric conditions allowed most of those winds to reach down to the surface downslope of the Little Rocky Mountains of southwest Phillips County.
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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 GGW wrote it up.
A favorable weather pattern steered a jet stream across the region. Atmospheric conditions allowed most of those winds to reach down to the surface downslope of the Little Rocky Mountains of southwest Phillips County.
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 Glasgow, MT wrote its last area forecast discussion before the first event at Dec 2, 3:04 AM MST, 2 hours 20 minutes earlier.
Area Forecast Discussion National Weather Service Glasgow MT 304 AM MST Mon Dec 2 2019 .DISCUSSION... Consensus continues surrounding a generally quiet weather period for this week across northeast Montana. Northwest to zonal upper flow regime will prevail with little or no precipitation for the next several days. Latest 00z ensemble 500mb heights point to upper ridging building stronger over the western U.S. toward the end of the week. Given large scale subsidence and rising heights, this guidance would point to a continuation of dry weather conditions as well as a gradual upswing in temperatures. Sure enough, consensus blends lead to highs in the mid 30s to low 40s by about Friday or Saturday, several degrees above average. Maliawco && .AVIATION... VFR conditions are expected today, though brief LLWS issues may occur early this morning. Otherwise, surface winds will be west, generally in a range between 5 and 15 kts today with occasional higher gusts. Maliawco && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && weather.gov/glasgow
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
At the Malta South US-191 DOT site MTMAL, sustained wind speeds of at least 40 mph were recorded each hour through most of the morning. Peak wind gusts of 57 mph were recorded from 930 AM to 935 AM.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2019Every state in 2019This day in weather historyWarnings in Montana, December 2019
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: 869170.