Eastern Wyoming
A few cities include: Cheyenne, Gillette and Torrington.
Local tornado season: Peaks between late May and late June.
Terrain: Hills, mountains, forests and some plains.
Road network: Fairly sparse and irregular.
Radar coverage: Good in southeastern Wyoming, bad farther north.
Eastern Wyoming is home to “High Plains magic,” as many storm chasers call it. Tornadoes are not particularly common in eastern Wyoming, but when they do occur, they can be very photogenic. Outside of tornadoes, picturesque supercells are commonplace, with large to very large hail being a potential hazard.
It does not take much to produce “magical” supercell thunderstorms in eastern Wyoming. Just enough low-level moisture combined with upslope flow trajectories and favorable deep layer wind fields will do the trick. With that said, road networks and terrain may make capturing such storms challenging, to say the least.
Terrain
Eastern Wyoming is where the plains meet the mountains. High elevation plains make up much of the area. The plains are sandwiched between the Black Hills to the northeast and multiple mountain ranges to the west. The Laramie Mountains in east-central to southeastern Wyoming help produce a unique terrain setup. Here, tornadoes can sometimes occur south or even west of the mountains.
Farther north, the Big Horn Mountains in north-central Wyoming are effectively the western cutoff of where one can realistically storm chase. Prairies cover much of the remainder of eastern Wyoming, but there are hills and forested areas mixed in. The terrain here is similar to that of parts of eastern Montana.
Road network
Eastern Wyoming has a fairly limited road network. A few parts of east-central and southeastern Wyoming have a manageable road network between roughly Cheyenne and Lusk. Elsewhere, road networks are sparse and wildly inconsistent. With roads spread out, taking sharp twists and turns, and forested areas coming into play, it can be very difficult to chase a storm.
One strategy might be to pick a location with a good view to watch a storm in the distance. Another could be to target eastern Wyoming when storm motions are slow, so road networks are not a major issue. It is not uncommon for slow-moving storms to drift over the High Plains. As a result, the lack of roads might not be a major issue.
Interstates 25, 80 and 90 are the major freeways that pass through eastern Wyoming. I-25 is approximately the western bounds of this chase zone. Mountains reside to the west, but a small area west of I-25 near Laramie can be storm chased. I-80 runs near the southern border of the state, connecting Laramie/Cheyenne with the Nebraska panhandle.
I-90 runs through rugged, hilly/forested terrain in northeastern Wyoming. There are a few places to exit along the way for a view, but that’s about it. If storm chasing along this corridor, it might be best to stick close to the interstate.
Radar coverage
Across eastern Wyoming, radar coverage ranges from good to non-existent. KCYS covers most of southeastern Wyoming, but that’s about all of the coverage you’ll get. KUDX attempts to cover parts of northeastern Wyoming, but the radar beam is partially blocked by the Black Hills. The result is that radar data is poor at best, if available at all, between northeastern and east-central Wyoming.
In summary, eastern Wyoming can be either a fun challenge or a painful ride depending on how you look at it. The area does experience supercell thunderstorms, including some photogenic tornadoes, but road networks can be tough. Add in limited radar data and rough terrain, and actually getting close to a storm here might be difficult.