Montana, 2020

Flooding in Montana, March 7 to 12, 2020

March 7 to 12, 2020 · NWS GGW · 2 events in 2 counties and zones

Recent snowmelt from northern Phillips County and central and northern Valley County contributed to many area creeks and streams running freely and feeding into the main-stem Milk River and Poplar River. Consequently, the lower Milk River through eastern Valley County and the Poplar River in western Roosevelt County both rose up to, and exceeded flood stage in the second week of March.

Where it happened

Every event with a place to put it. 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

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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 GGW wrote it up.

Recent snowmelt from northern Phillips County and central and northern Valley County contributed to many area creeks and streams running freely and feeding into the main-stem Milk River and Poplar River. Consequently, the lower Milk River through eastern Valley County and the Poplar River in western Roosevelt County both rose up to, and exceeded flood stage in the second week of March.

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 Glasgow, MT wrote its last area forecast discussion before the first event at Mar 7, 9:01 AM MST, 3 hours 15 minutes earlier.

Area forecast discussion, Mar 7, 9:01 AM MST, 3 hours 15 minutes before
Area Forecast Discussion
National Weather Service Glasgow MT
901 AM MST Sat Mar 7 2020

.DISCUSSION...
Morning update...
Minimal changes this morning as going forecast was in pretty good
shape.

Questions for the afternoon package will include the precipitation
tonight and tomorrow and temperature trends in the week ahead.

Avery

Previous discussion...
Upper ridge will move to the east today. Low pressure system will
develop over central and eastern Montana. Temperatures will be
warm today ahead especially in the south.

Another warm day for some Saturday before a cold front drops in,
bringing a cooler day Sunday. Precipitation may occur in the
cooler air Saturday Night near the Canadian border.

A cold front dropping south through Alberta and Saskatchewan this
morning will slow today as it becomes parallel to the SW flow
aloft. A wave in the SW flow aloft will move through Montana
tonight pushing the surface low and cold front to the east. Most
of the moisture and upper level dynamics will stay to the west and
north of the forecast area which will limit the best chances for
mixed precipitation to the northern parts of the forecast area.
Any precipitation that occurs tonight will start as rain and could
become sleet or freezing rain before temperatures become cold
enough for all snow. With light precip amounts expected, will hold
off on any advisories for now.

Sunday will be much colder with highs from the upper 20s to mid
40s.

The upper trough will be over the northern Rockies Monday with a
few rain and snow showers and another wave on Tuesday could bring
a slight chance of light rain or snow to parts of the region.

Wednesday and Thursday will be mainly dry in WNW flow aloft.
Another upper trough late in the week will bring chances for rain
and snow. Forrester

&&

.AVIATION...

FLIGHT CAT: VFR most of the time. Areas of MVFR late tonight and
Sunday morning.

Expect mainly high clouds today. Low clouds will move in with the
cold front tonight. Winds will be light and variable this morning
with east to SE winds 5 to 10 knots this afternoon in most areas
and SW at KGDV. Winds will turn NW with the cold front tonight.

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

weather.gov/glasgow

The radar

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

Open the radar archive at this moment

Event by event

2 flood. Local standard time, as filed.

Flood, Valley

When
March 7, 12:16 PM MST to March 12, 9:38 AM MST
Where
Valley County, 1.22 mi W of Nashua to 0.34 mi W of Nashua
Cause
Heavy Rain / Snow Melt
Reported by
River/Stream Gage
Coordinates
48.133, -106.376

Excessive snow melt caused flooding at the river gauge on the Milk River near Nashua (NSHM8). The gauge recorded river levels rising above the flood stage of 20.0 feet at 12:16 PM MST on March 7th. The river crested at 21.75 feet at 10:00 PM MST on March 8th. River levels dropped back down below flood stage at 9:38 AM MST on March 12th.

Flood, Roosevelt

When
March 10, 9:38 AM MST to March 11, 3:30 AM MST
Where
Roosevelt County, 0.98 mi N of Poplar to 1.29 mi SW of Poplar Arpt
Cause
Heavy Rain / Snow Melt
Reported by
River/Stream Gage
Coordinates
48.114, -105.204

Excessive snow melt caused flooding at the river gauge on the Poplar River near Poplar (PLRM8). The gauge recorded river levels rising above the flood stage of 16.0 feet at 9:38 PM MST on March 10th. The river crested at 16.2 feet at 11:30 PM MST on March 10th. River levels dropped back down below flood stage at 3:30 AM MST on March 11th.

What these are

Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

More

Every storm in Montana in 2020Every state in 2020This day in weather historyWarnings in Montana, March 2020

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 2026-09-24. Each event’s entry at NCEI: 877852, 877855.