Chase Day 6 - SE Wyoming into NE Colorado

MON 02 JUN 

We left Hays (KS) reasonably early (8am) to get closer to our target in the vicinity of the Nebraska / Wyoming / Colorado border. After lunch in North Platte (NE) we continued to push west, stopping briefly at Big Springs (NE) and Sidney (NE) to reassess the situation. By mid-afternoon a few severe-warned supercell thunderstorms had developed in eastern Wyoming, and we opted to follow the Tail End Charlie at Pine Bluffs (WY) which offered some lovely structure. 

SPC forecast issued 16:30Z 02 June 2025

Congestion on I-80 where the supercell, and associated heavy rain and large hail, crossed the interstate

Road options were rather sparse so it became difficult to keep up with this first storm as it crossed I-80 and headed more SE'wards across the Colorado border. We headed back east to Sidney then south to Sterling (CO), by which point our first storm had all but died but superseded by several new cells that had built further south into Colorado. As we neared Sterling, the supercell nearest us came into view with a ragged wall cloud - this piqued our interest! We nudged west a little, to park up several times and watch this supercell wrapping up and producing yet again some fantastic structure. There were several occasions where it looked like this supercell might produce a tornado (and was appropriately warned), and despite a few spotter reports we never saw anything particularly convincing... we did see a brief gustnado (which appears to have been reported as a "landspout"). The inflow winds significantly cranked up, and we measured 50 mph on a handheld Kestrel, with plenty of lifted dust from the fields.

Tornado warnings were issued for the supercell as it approached and move through Sterling (CO)

Once the supercell approached Sterling it weakened fairly quickly, as numerous additional cells developed in the vicinity. At this point we decided to leave it and undertake a fair few miles to get us slightly closer to tomorrow's target which is many hours away down near the red river (Oklahoma / Texas border).