Jeremy Perez
Supporter
On Sunday, October 21st, tropical moisture was in place over Arizona, with a low impinging on it from the west. So southwest flow was in play over the Mogollon Rim Convergence Zone (MRCZ). Work had been a bear and I’d been dealing with a chest cold the previous few days so I wasn’t exactly eager to get out. But I felt better by Sunday morning, and was watching conditions and browsing HRRR/UofA WRF CAMs. HRRR had been pretty set on some stronger storms initiating and moving across the MRCZ, from Twin Arrows through Winslow. RAP surface vorticity suggested elevated vorticity in that same area. WRF CAMs didn’t have the same consistent signal, but with HRRR being so interested in it, I figured I’d mosey out there around 1-2PM and see what was up.
While I was out running an errand, radar showed convection trying to fire. It was pulsing inside a notch in the convergence boundary that had formed southeast of Flagstaff around 12:30PM. That was earlier than I expected, so by the time I was on I-40 heading east, one cell was already looking pretty good. With 30ish knots of bulk shear, I was mainly interested in some brief structure.
— 1947Z —
Reflectivity scan showing notched boundary with developing cell
As I got near Buffalo Range Road, about 12 miles from the cell, it looked like a funnel was poking out of the southern tip of the base. So I started the cell phone rolling video on it.
About a minute later, 2058Z, dust appeared on the horizon where the funnel was aimed, so landspout! You never know how much time you’ve got, but I didn’t want to pull over on the interstate. Fortunately, the Two Guns exit was just a couple more minutes down the road. Once I got there, I realized terrain to the west was going to hide the point of ground contact, but I couldn’t waste more time hunting down a better spot.
— 2058Z —
Funnel and clear evidence of dust/debris
— 2100Z —
Landspout strengthening beyond Two Guns
The condensation funnel gradually stretched down into the lengthening dust column. With the sun reflecting off orange dust and white vapor, it was more stunning than I could have hoped for an Arizona tornado. It’s one of the sights I imagine when heading out for a Plains chase — wondering if I’ll catch a high-definition, colorful rope-out among other things. And there I was, 30 miles from home, watching it happen on a Sunday afternoon.
— 2104Z —
Looking east-southeast from the east side of Two Guns

While I was out running an errand, radar showed convection trying to fire. It was pulsing inside a notch in the convergence boundary that had formed southeast of Flagstaff around 12:30PM. That was earlier than I expected, so by the time I was on I-40 heading east, one cell was already looking pretty good. With 30ish knots of bulk shear, I was mainly interested in some brief structure.
— 1947Z —
Reflectivity scan showing notched boundary with developing cell

As I got near Buffalo Range Road, about 12 miles from the cell, it looked like a funnel was poking out of the southern tip of the base. So I started the cell phone rolling video on it.
About a minute later, 2058Z, dust appeared on the horizon where the funnel was aimed, so landspout! You never know how much time you’ve got, but I didn’t want to pull over on the interstate. Fortunately, the Two Guns exit was just a couple more minutes down the road. Once I got there, I realized terrain to the west was going to hide the point of ground contact, but I couldn’t waste more time hunting down a better spot.
— 2058Z —
Funnel and clear evidence of dust/debris

— 2100Z —
Landspout strengthening beyond Two Guns

The condensation funnel gradually stretched down into the lengthening dust column. With the sun reflecting off orange dust and white vapor, it was more stunning than I could have hoped for an Arizona tornado. It’s one of the sights I imagine when heading out for a Plains chase — wondering if I’ll catch a high-definition, colorful rope-out among other things. And there I was, 30 miles from home, watching it happen on a Sunday afternoon.
— 2104Z —
Looking east-southeast from the east side of Two Guns

