An interesting period for May 10 and 11. I captured an incredible mothersip supercell May 10 near Grand Island . This storm formed on the triple point and became one of the prettiest supercells, structure wise, that I had ever seen. It almost immediately started rotating and became severe quickly after it formed. There were many reports of tornadoes with this storm, none of which I believe are true. It was fairly high based its entire life.
On May 11 we left Kearney mid morning headed south towards Stockton , Kansas . When we arrived it was 81/68 with a nice southeast wind early afternoon. We watched as soft towers would go up and get sheared over. We ended up chasing the cell that was tornado warned northwest of Stockton . These cells were high based, and not very organized. As they crossed front, they became even more elevated and did not much of anything.
Mid afternoon we blew of this junk and headed west to the triple point as cell exploded there. We arrived near Benkelman and came over a hill to catch a glimpse of a weak skinny tornado west of town. The storms looked linear somewhat with a shelf cloud racing northeast. Updrafts were visible behind the shelf. Then something weird happened. My temp and dewpoint went from 63/59 to 71/64 in a matter of 1 minute. All of a sudden an updraft base starting rapid cascading motion, then rapid anticyclonic twisting and turning. Then a loud waterfall sound formed and a few seconds later a tapered cone funnel formed almost overhead. As quick as all the happened, less than a minute, a debris cloud formed in a field just to the southwest of the van. RFD hit the van on the NORTH side of the tornado, which we determined WAS anticyclonic!
We blasted north away of this northeast moving tornado as condensation developed to the ground. Our view out the west side of the van was one of condensation lifting with multiple vortices twisting and turning as debris, old corn stalks and tumbleweeds went flying up and rapidly rotating around the vortex! This tornado was no more than 100 yards from us and closing. We drove at a fast pace to get away from this tornado and managed to get a quarter mile away and we stopped. It immediately dissipated as the funnel rapidly vanished. This entire sequence happened in 3 minutes!