Even though a few light rain showers occurred in the month of April, the continued lack of significant precipitation throughout the month enabled the drought across the region to worsen and spread westward through most of northeast Montana.
Every event with a place to put it; 13 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.
Even though a few light rain showers occurred in the month of April, the continued lack of significant precipitation throughout the month enabled the drought across the region to worsen and spread westward through most of northeast Montana.
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 Mar 31, 8:06 PM MST, 3 hours 54 minutes earlier.
Area Forecast Discussion National Weather Service Glasgow MT 906 PM MDT Wed Mar 31 2021 .DISCUSSION... EVENING UPDATE: Dry weather expected in the near term. The going forecast is maintaining dry conditions coupled with low RHs and gusty winds with critical fire weather expected tomorrow. Rux Afternoon Update: There was enough confidence added this afternoon with adjustments to winds and RH for tomorrow that fire weather will be critical in the afternoon, thus necessitating an upgrade to a Red Flag Warning. For Friday, while conditions are not quite as much of a slam dunk as Thursday, so to speak, with criticality for fire weather concerns, the western half of the region looks more likely to reach thresholds for an RFW, so a new Fire Weather Watch for the western half of the area was issued for Friday afternoon. Otherwise, the rest of the forecast was left alone with a fairly quiet pattern expected. Cliff PREVIOUS DISCUSSION: Following a cold morning across NE Montana, at least when compared to recent days, temperatures will be on the upswing as upper ridging becomes established over the next several days. While upper ridging will guide dry weather and warmer temperatures across the region, with highs into the 60s and 70s by Thursday and beyond, this pattern will begin to raise other forecast challenges. Breezy conditions combined with low relative humidity and dry fuels will lead to high fire weather danger on Thursday. As such, have continued the Fire Weather Watch. This threat may linger into Friday, though there is somewhat greater uncertainty on wind speeds at this time. For the weekend, warm and dry weather will also remain in place, though a cold front may approach before the weekend is through with cooler temperatures for early next week. && .AVIATION... LLWS: Some shear potential at KOLF overnight from 09Z-12Z, out of the west at 30kts. Expected Flight Category: VFR Synopsis: Pleasant flying conditions expected most of the period, with mostly clear to partly cloudy skies through Thursday. Winds: Light winds under 10 kts for much of the area will become west-southwest Thursday at 10-20 kts. Cliff/Rux && .FIRE WEATHER... For Thursday, critical fire weather concerns are expected with southwest winds likely to be 15-20 mph most of the afternoon, and relative humidity bottoming out in the teens across the region. Winds most of the afternoon are likely to be higher than the RH, thus necessitating an upgrade to RFW region-wide for Thursday. On Friday, winds are expected to be lighter than Thursday overall, but moreso in the east than in the west. With lower winds, even though RH is likely going to be comparable to Thursday, conditions are not expected to be critical for the eastern half of the region. In the western half, however, there does seem to be some indication that winds could exceed RH, thus it was deemed necessary to put out a Fire Weather Watch for Fire Weather zones 134-137 Friday afternoon. Cliff && .GLASGOW WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 9 PM MDT Thursday for MTZ120-122-134>137. Fire Weather Watch from Friday afternoon through Friday evening for MTZ134>137. && weather.gov/glasgow
The national radar mosaic for the moment the first event began.
13 drought. Local standard time, as filed.
To start the month of April in Sheridan County, ongoing drought conditions (D2-Severe) worsened to D3-Extreme across the entire county, which persisted through the end of April.
To start the month of April, ongoing drought conditions (D3-Extreme) in the far southeast corner of Eastern Roosevelt county and D2-Severe drought everywhere else, worsened to fill all of Eastern Roosevelt County with D3-Extreme drought, which persisted there through the end of April.
To start the month of April, ongoing drought conditions (D3-Extreme) in the northeast corner of Richland County and D2-Severe everywhere else, worsened to spread D3-Extreme drought to all but the northwest corner of the county. During the last week of April, D3-Extreme drought had spread to cover the entire county.
To start the month of April, ongoing drought conditions (D2-Severe), worsened to D3-Extreme for all but the southwest corner of Wibaux County. By mid-April, D3-Extreme drought had spread to all of the county, which persisted through the end of the month.
To start the month of April, ongoing drought conditions (D2-Severe), worsened to D3-Extreme along the far eastern edge of Daniels County. In the second week of April, D3-Extreme drought spread westward through the eastern half of the county. By the last week of April, D3-Extreme drought had spread through all of the county, which persisted through the end of the month.
To start the month of April, ongoing drought conditions (D2-Severe), worsened to D3-Extreme in eastern and northeastern portions of Western Roosevelt County. By the last week of April, D3-Extreme drought had spread westward through all of Western Roosevelt County, which persisted through the end of the month.
To start the month of April, ongoing drought conditions (D2-Severe) for all but the southwestern portion of McCone County, now worsened to D3-Extreme drought in the far southeastern corner of the county. In the third week of April, D2-Severe drought had filled in the southwestern portions of the county, and D3-Extreme drought spread further through more of southeastern McCone County. By the last week of April, D3-Extreme drought had spread through the eastern half of the county, which persisted through the end of the month.
To start the month of April in Dawson County, ongoing drought conditions (D2-Severe) worsened to D3-Extreme drought for all but the far northwest, southwest, and southeast corners of the county. By the third week of April, D3-Extreme drought had spread to all but the far northwest corner of the county. By the last week of April, D3-Extreme drought had spread through all of Dawson County, which persisted through the end of the month.
To start the month of April, ongoing drought conditions (D2-Severe) from the northeastern half of Prairie County, had spread into all but the western edge of the county. By the third week of April, D2-Severe drought had filled in the western edge, and the remainder of the county had worsened into D3-Extreme drought, which persisted through the end of the month.
Ongoing drought conditions (D2-Severe) through all of Northern Valley County remained through the first week of April. By the second week of April, the western two-thirds of Northern Valley County worsened into D3-Extreme drought. By the last week of April, all of Northern Valley County worsened into D3-Extreme drought, which persisted through the end of the month.
Ongoing drought conditions (D2-Severe) through all but the southwestern corner of Central and Southern Valley County continued through the first week of April. By the second week of April, the central to northwestern section of Central and Southern Valley County worsened into D3-Extreme drought. By the third week, D2-Severe drought filled in the southwestern corner. By the last week of April, D-3 Extreme drought filled in the central and eastern section of Central and Southern Valley County (basically all areas near and north of US Highway 2).
Ongoing drought conditions (D2-Severe) through all of Northern Phillips County remained through the first week of April. By the second week of April, the eastern two-thirds of Northern Phillips County worsened into D3-Extreme drought, which persisted through the end of the month.
Ongoing drought conditions (D2-Severe) over the northeastern third of Central and Southeastern Phillips County remained through the first week of April. By the second week of April, the far northeastern portion of Central and Southeastern Phillips County worsened into D3-Extreme drought. By the third week, D2-Severe drought had expanded into western and southern portions. By the last week of April, D-2 Severe drought expanded into the far northwestern portions of Central and southeast Phillips 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, April 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: 952022, 952023, 952024, 952025, 952026, 952027, 952028, 952029, 952031, 952039, 952165, 952184, 952185.