There were several tornadoes in northeastern Montana on Friday evening.
It will take a couple of days for the National Weather Service in Glasgow to investigate and release a report regarding Friday's severe weather, but based on photos we received, it looks like there were at least three if not more tornadoes.
There were twin tornadoes south-southeast of Opheim in Valley County, and there was a tornado in Daniels County south of the Richland area. There was also a possible tornado near Larslan in Valley County.
The first Tornado Warning was issued at 6:47 p.m. for the northern part of Valley County, with the last Tornado Warning expiring at 8:15 p.m.
Tornado warnings were in effect for northeastern Valley County, southwestern Daniels County, and northwestern Roosevelt County during this 88-minute period.
It seems like most of the tornadoes occurred in rural areas, so most of the damage was just to farmland.
However, there were reports of broken trees, downed power lines, and a barn being ripped apart near the Larslan area. It appears that the Larslan area received the most tornado damage.
Tornadoes were not the only threat with these storms as there was also torrential rainfall, strong winds with gusts up to 60 mph, and large hail.
One viewer stated that baseball to softball-sized hail fell north of Larslan, and our radar indicated that hail as large as a grapefruit may have been falling at one point.
Tornadoes in Montana
Montana usually has about a dozen tornadoes each year. Unlike those in "Tornado Alley" in the central part of the country, most Montana tornadoes are relatively small and usually touch down in sparsely populated areas.
Tornadoes are categorized on the Enhanced Fujita (EF) Scale from EF-0 to EF-5, based on their destructive power. EF-0 tornadoes are the weakest, while EF-5 tornadoes are the most powerful.
In 2022, an EF-2 tornado hit the community of Glentana in Valley County, causing property damage (link). The tornado was on the ground for eight miles and had an average path width of 457 yards. The maximum wind speed associated with this tornado was 120 miles per hour.
In 2016, an EF-3 tornado hit the town of Baker in southeast Montana. In 2015, a small tornado hit near Sidney in Richland County in eastern Montana, injuring one person and causing some damage.
In June 2010, a tornado hit Billings, causing significant damage to the MetraPark facility. Just several weeks later, two people were killed when a tornado struck a family ranch near Reserve in northeastern Montana.
Montana's tornado season generally spans from late May through early August. The two key ingredients for tornado formation are low-level moisture and wind shear.
Wind shear is the change in wind direction with height up to the mid-levels of the atmosphere.
Patrick Gilchrist, the warning coordination meteorologist for the National Weather Service in Glasgow, said, "When it comes to tornadoes in Montana, it's really about moisture. So to get tornado development, we really want a moist layer right at the surface of the Earth at the lowest levels. That is provided actually by the Gulf of Mexico."
The likelihood of tornadoes increases in eastern Montana, due to the proximity to the Gulf of Mexico, not the change in topography. Higher terrain in Western Montana actually acts as ignition for severe weather outbreaks as it forces the air to move vertically creating lift in the atmosphere. The severe weather outbreaks can often last through the night, traveling as far as Minnesota.
While tornadoes are less common in central Montana, the threat still exists. There have been a few notable events in recent history. An F2 moved through Lewistown back in 1999 and a series of F3 tornadoes southeast of Big Sandy in Chouteau County back in 1988.
Damage assessments are utilized in determining the tornadoes scale, which can be difficult given the rural nature of eastern Montana.
