Guess I'll join in on the posting of ceiling fan generated vortices. Here is some close up ground footage on a low friction surface.

Intense helical vortex generated by a strong updraft.

Very cool V shaped downdraft interactions.

Intertwined helical structure caused by the strong two cell downdraft.

An awesome helical vortex happening at ground level.

Gorgeous tornado minutes ago. #IAwx

This storm literally produced in these TD spreads with 1000m + LCLs. The simple way to put it, all you need is vorticity and an updraft and essentially a tornado is possible. Crazy

I’m still very new to editing photos but here’s some edits I made of last weeks supercell/tornado in Lewistown Illinois! #wxtwitter

Wooooo Weee, this IS my best photo of all time. Wow.... #nmwx #wxtwitter #Thunderstorm

Oh...my...gosh....it just keeps getting BETTER! I really don't even think what I just saw was real. #nmwx #wxtwitter #thunderstorm

Amidst the chaos of last night, I have increasing confidence that a large tornado started around the 9:45 - 10:00 PM time frame and lasted 1-2 minutes before getting wrapped in rain. This was taken slightly North West of Grady on road 469 NWS Albuquerque #nmwx #wxtwitter

Unbelievable sprites occurring over the powerful MCS in Oklahoma last night. I’m still at a loss for words after this one. #okwx

So many clear air bolts and I'm 3 hours away. Sadness. Pain even.