The Santana Wind

The Santa Ana or Santana wind of Southern California is a foehn, a wind that occurs on the downward slope of a mountain range. As far as I can tell, the Santa Ana wind originates far to the east and has  nothing to do with the city of Santa Ana. 

My generation in Los Angeles grew up calling the wind "Santana," although the other name is apparently older. 

My wife and I moved to New York to work and then back west to retire in Northern California. I read in the local newspaper that Santa Rosa sometimes got a "Santa Ana wind." That made no sense to me--we were 500 miles from Santa Ana. I paid no attention until the Tubbs fire--driven by a foehn--three years ago killed about 50 people in Sonoma County. That's when I first became aware of the term "fire season."

California has always had massive fires, I suppose, during the part of the year when vegetation is most dry. With global warming, that period has become dryer and longer.  Back in 1957 a Santa Ana in Southern California blew from November 21 to December 4. Wind gusts reached 100 mph. Fires raged out of control. People died. It was a lot like the Tubbs fire. The difference today is that many more people have built homes near or in the woods. And we are experiencing wind-driven wild fires in towns.

About all this, Joan Didion long ago wrote, "The wind shows us how close to the edge we are."

s

A föhn or foehn (UK: /fɜːn/,^[2][3] US: /feɪn/) is a type of dry, warm, down-slope wind that occurs in the lee (downwind side) of a mountain range.

Föhn can be initiated when deep low-pressure systems move into Europe, drawing moist Mediterranean air over the Alps.

It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of its moisture on windward slopes (see orographic lift). As a consequence of the different adiabatic lapse rates of moist and dry air, the air on the leeward slopes becomes warmer than equivalent elevations on the windward slopes. Föhn winds can raise temperatures by as much as 14 °C (25 °F)^[4]in just a matter of hours. Switzerland, southern Germany and Austria have a warmer climate due to the Föhn, as moist winds off the Mediterranean Sea blow over the Alps.