Name: Winter Storm in Montana, April 16 to 18, 2011
Start: 2011-04-16T19:00
End: 2011-04-18T13:00
Location: Montana

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 TFX wrote it up.

A Pacific storm system brought heavy snow to the Rocky Mountain Front. Snow amounts up to a foot were reported.

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 Great Falls, MT wrote its last area forecast discussion before the first event at Apr 16, 4:35 PM MST, 2 hours 25 minutes earlier.

Area forecast discussion, Apr 16, 4:35 PM MST, 2 hours 25 minutes before

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Hazardous weather outlook, Apr 16, 5:24 PM MST, 1 hour 36 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
624 PM MDT SAT APR 16 2011

MTZ047-171145-
BLAINE-
624 PM MDT SAT APR 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
MONTANA.

A FLOOD ADVISORY REMAINS IN EFFECT FOR CREEKS AND SMALL STREAMS IN
BLAINE COUNTY.

A FLOOD WATCH IS ALSO IN EFFECT FOR THE MILK RIVER NEAR HARLEM.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE FLOOD WATCH FOR THE MILK RIVER NEAR HARLEM REMAINS IN EFFECT
UNTIL FURTHER NOTICE.

THE FLOOD ADVISORY REMAINS IN EFFECT THROUGH SUNDAY AFTERNOON.

.SPOTTER INFORMATION STATEMENT...

REPORTS OF FLOODING WOULD BE GREATLY APPRECIATED.

MTZ008>015-044>046-048>055-171145-
BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL-
CASCADE-CHOUTEAU-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-
TOOLE-LIBERTY-EASTERN PONDERA-SOUTHERN ROCKY MOUNTAIN FRONT-
EASTERN TETON-JUDITH BASIN-FERGUS-JEFFERSON-BROADWATER-MEAGHER-
GALLATIN-
624 PM MDT SAT APR 16 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA.

.DAY ONE...TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

In the hours before

Local storm report, Apr 16, 3:54 PM MST, 3 hours 6 minutes before

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Event by event

2 winter storm. Local standard time, as filed.

Winter Storm, North Rocky Mountain Front

When: April 16, 7:00 PM MST to April 18, 1:00 PM MST
Where: North Rocky Mountain Front forecast zone
Reported by: Trained Spotter

Twelve inches of snow fell at Browning.

Winter Storm, Southern Rocky Mountain Front

When: April 16, 7:00 PM MST to April 18, 1:00 PM MST
Where: Southern Rocky Mountain Front forecast zone
Reported by: Mesonet

Nine inches of snow fell at Bynum 23W (the Waldron SNOTEL site - elevation 5600 feet).

What these are

Winter Storm: A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

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

The same day elsewhere

More

Every storm in Montana in 2011 Every state in 2011 This day in weather history Warnings in Montana, April 2011

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: 299722, 299729.