Eastern Montana
A few cities include: Broadus, Glasgow and Miles City.
Terrain: A variety of plains, hills, rivers, forests and mountains.
Local tornado season: Sporadic through June and July, sometimes August.
Road network: Sparse and inconsistent with some large gaps.
Radar coverage: A large gap in southeastern Montana, fair elsewhere.
Eastern Montana establishes the northern bounds of the High Plains in the United States. Tornadoes occasionally occur in eastern Montana, but they are less common here than anywhere else surveyed in this guide.
Some years might have a setup or two that produce tornadoes in eastern Montana, while other years may only have a stray tornado or two the entire season. With that said, given the sparsely populated landscape and eye-catching terrain, it can be a great area to witness a summer supercell thunderstorm.
Terrain
The terrain in eastern Montana is as rugged as it gets in the High Plains. Far eastern into northeastern Montana is somewhat flat in spots, but rivers, hills and forests are scattered throughout the area. The Missouri River forms Fort Peck Lake around the Piney Buttes, creating an area that is not very chaser-friendly in northeastern Montana. Rivers and the Bull Mountains to the south create more terrain obstacles. The terrain tends to be the least obtrusive in far northern sections of eastern Montana and eastward near the border with North and South Dakota.
Road network
If the terrain was not challenging enough, the road network poses an even bigger problem. Given the terrain and sparsely populated landscape, roads follow irregular paths and gaps between paved roadways can be quite large. The area along and north of US-2 in northeastern Montana has a manageable road network in spots, but even here, terrain and some road gaps can make it tricky to get close to a storm.
Elsewhere, there is not much to work with, so the chasing strategy will often be to hope that storms will occur close to one of the few available primary roadways. Interstate-94 is the main freeway across the area, as it generally parallels the Yellowstone River and connects Montana to North Dakota. Interstate-90 connects eastern Montana with Wyoming, but terrain in unfavorable for storm chasing in that area.
Radar coverage
The only major radar site in eastern Montana is KGGW. That site provides coverage for most, but not all, of northeastern Montana. That leaves a glaring hole in radar coverage across southeastern Montana. In fact, it is the largest gap in National Weather Service radar coverage anywhere in the central United States. The North Dakota Water Commission’s radar site out of Bowman, ND can lend some coverage in far eastern Montana. Likewise, KUDX’s radar is able to lend some distant coverage to the far southeastern corner of Montana.
In summary, eastern Montana can be a challenging place to storm chase. While are there are some flatter areas, the terrain becomes hilly and even mountainous with westward extent. A limited road network through most of the area and a lack of radar data in southeastern Montana can make storm chasing here quite difficult.