Tornado Alley (PROG)

[F6]

longhorn0206 -- that was one of those days -- folks knew there were going to be tornadoes, probably strong and potentially violent, but until it started to happen . . .

4/26/91 -- perfect conditions, essentially unlimited warm high-dewpoint inflow on the surface and HUGE energy aloft, and just enough mid-level cap so there had been no initiation up into the peak heating of late afternoon -- late afternoon, well out ahead of the dryline and deep into the deep moisture, triggered and then driven by a powerful surge in the already very strong flow aloft, precisely four towering cumulus buildups manage to break the cap and immediately commence rotation and explosive intensification, each discrete, all by itself, just far enough, about 40 miles, from the next -- from the Andover/Wichita KS storm in the north, south to the one they called the Winfield storm that started in extreme northern OK and tracked generally ENE (as all the storms tracked) into extreme southern KS, south to the Red Rock storm north of Oklahoma City in my sig pic on the left, to the Oolagah storm to the southeast from there

each storm produced a massive long-track F5/F6 tornado, for a time all 4 on the ground at once

because it did hit developed areas (fortunately, the others did not), the Andover/Wichita storm did the most damage and took more than 20 lives, but it was actually the runt of the litter -- still a plenty massive storm but at least generally under a mile wide, and also not as long-lived as the others

the Red Rock, 'my' storm (radar echo topped out at 68,000 feet), was about 3/4 mile wide and getting bigger quickly in the sig pic, within minutes was about 1.5 miles wide as it passed in front of us (moving to the right; flattened, literally bent flat on the ground at the ground, the little '200' mile marker on I-35 [that highway]), max damage path width per survey about 1.75 miles

the Oolagah was a bit over a mile wide

which leaves the Winfield -- every bit of two and one half miles in diameter on the ground, and not just for a minute or two, but for an extended period of time and length of track -- and apparently also the strongest storm of the day in terms of the radar data -- I've seen video -- it really was that big -- . . .

and there was that other storm that late afternoon and evening, up north in Nebraska -- put down one that approached 2 miles wide somewhere E to NE of North Platte

it was quite a day -- there certainly have been bigger outbreaks, quite a few -- but I'm not sure there's ever been another day in our records quite like that