
© YouTube/Mike Olbinski (screen capture)
All spring I chase storms across the United States to collect footage of supercells, lightning, tornadoes and whatever I might find. Generally I don't release any time-lapse clips from those chases until I put out my final end of season compilation film. But last night in North Dakota was too unreal to let sit on my hard drive for months.
We were chasing northeast of Bismarck, North Dakota and as storms were dying out, we decided to go for a lone cell on the backside of a line of storms. We knew it had a hail core on it and we were hoping that we might get some nice sunset color at least on the storm as it moved past us, and hopefully some lightning bolts. But we had no idea what we were about to encounter. The clouds were taking on a very different, curvy, wave-like appearance and suddenly we knew what we were seeing.
Undulatus asperatus clouds are a rare phenomenon and actually the newest named cloud type in over 60 years. I've seen tons of photos of them, but never anything like what we witnessed last night. We had a storm with hail in front of us and flashing lightning which was fantastic. But then we had this layer of undulatus clouds flowing across our view.
Comment: Less than one week ago 16 people died in Moscow, with at least another hundred injured, after the worst storm to hit the city in living memory, and probably the worst since the 19th century. See also:
Updates: Worst ever natural disaster: Death toll from Moscow storm rises to 16 (VIDEOS)