The seasonal weather pattern continued to steer most precipitation away from the northeast corner and the eastern edge of Montana through the month. For some locations, severe drought conditions crept slightly further toward the west by the last week on the month (Wibaux, Richland, and Western Roosevelt Counties).
Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The seasonal weather pattern continued to steer most precipitation away from the northeast corner and the eastern edge of Montana through the month. For some locations, severe drought conditions crept slightly further toward the west by the last week on the month (Wibaux, Richland, and Western Roosevelt Counties).
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 31, 2:07 PM MST, 9 hours 53 minutes earlier.
Area Forecast Discussion National Weather Service Glasgow MT 207 PM MST Thu Dec 31 2020 .DISCUSSION... AFTERNOON DISCUSSION: Overall afternoon forecast package has little change from the overnight package. Main thing is a slow warm up and dry forecast with confidence dropping off pretty quickly around Monday night when ensembles begin major disagreement. Even though they disagree heavily the broad majority still stay relatively warm through these periods. So, at least the confidence in that is average to a little higher. GAH 800AM UPDATE: Main change to the forecast this morning was to bring up hourly temps from roughly teens and 20s to the 20s and 30s. Cloud cover has kept temperatures up through most of the night and there appears to be no major breaks in the clouds moving forward for the next 3-5 hours. With light radar echos across the area and trace precip appearing on station have also decided to raise slight chance PoPs up to chance for the same time frame. Due to the rise in morning surface temperatures precipitation has switched over to rain just south of the Missouri. However, as ground is likely frozen, most of this will freeze on contact generating black ice and slick roads this morning even if most of the QPF is trace to light. GAH MORNING DISCUSSION: A weak shortwave trough will move through Northeast Montana this morning. This will bring a chance for some light snow showers before tapering off during the afternoon. Little in the way of accumulation is expected. A series of ridges and shortwave troughs will continue through the forecast period with a warming trend continuing through the weekend. Highs this weekend will generally be in the 40s. Breezy westerly winds are expected Saturday with wind gusts to at least 40 mph a possibility. Above normal temperatures and dry conditions look to continue into next week. -Mottice/RAE && .AVIATION... LAST UPDATED: 2030Z FLIGHT CAT: VFR-MVFR DISCUSSION: Mainly VFR. A few ceilings are flirting with temporary MVFR but if these conditions are reached the ceilings should only stay there for an hour or two. There is a chance for FOG in the Milk and Missouri Rivers Valleys tonight which may affect KGGW or KOLF briefly. Not enough models agree on this, so confidence is low and it hasn't yet been added to the TAFs. WIND: West at 10 to 15 kts in the afternoon. Then veering to west to northwest at 10 kts or less overnight. Backing to west to southwest at 5 to 15 kts again Friday afternoon. GAH && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && weather.gov/glasgow
The national radar mosaic for the moment the first event began.
6 drought. Local standard time, as filed.
Drought conditions (D2-Severe) persisted across all of Sheridan County through the entire month of January.
Drought conditions (D2-Severe) persisted across all of eastern Roosevelt County through the entire month of January.
Drought conditions (D2-Severe) persisted across central and eastern portions of Daniels County (generally near and east of MT Highway 13) through the entire month of January.
Drought conditions (D2-Severe) persisted over the eastern edge of Richland County through the month. During the last week of the month, drought conditions (D2-Severe) expanded westward across all but the southwest corner of the County.
Drought conditions (D2-Severe) persisted over central and northeastern portions of western Roosevelt County through the entire month. During the last week of the month, drought conditions (D2-Severe) expanded westward into all but the western edge of western Roosevelt County.
Drought Conditions (D2-Severe) over the northeastern half of Wibaux County persisted through the entire month. During the last week of the month, drought conditions (D2-Severe) expanded westward through the remainder of Wibaux County.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2021Every state in 2021This day in weather historyWarnings in Montana, January 2021
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: 936039, 936041, 936042, 936052, 936055, 936058.