Tornado Alley (PROG)

[DesertDrifter]

Tornadoes do indeed occur on occasion even in mountainous terrain that has very high relief. I have personally witnessed a few funnel clouds pass over the highest points of the coast range and the fault block mountains to the east in the sierras. On one occasion one touched down and leveled some huge stands of grand fir and even-aged Douglas-fir, all neatly blown over in a spiral pattern about 1/4 mile across as it skipped along several ridges on Bluff Creek in Siskiyou County, California. It was a bugger walking through that windfall to mark the helicopter salvage sale that followed.

But the majority of the twirlies we see in the large mountains are just dust devils of large size that are due to convective surface heating, and not the product of interacting air masses like the ones in the east. I totally agree that the hills of texas give no immunity to tornadic winds. Even in texas, Ferrel's Law and the coreolis effect apply.