“Here come those Santa Ana winds again” (Steely Dan, Babylon Sisters). 
Named after Southern California’s Santa Ana Canyon, the Santa Ana is a blustery, dry and warm (often hot) wind that blows out of the desert. The winds usually come during California’s cold season, between September and April.
Most people believe that the desert brings the hot wind, but in fact the desert is cold at this time of year. High pressure builds in the LA Basin, causing the cold air to sink. The air is forced into a down slope where it compresses quickly, warming the air, and losing humidity. That dry air picks up speed through the passes and canyons, and there you have your Santa Ana wind. The wind usually blows off the water from west to east, but the Santa Anas blow from East to West. Rising temperatures can reach well into the 80s, 90s and even 100s when these winds blow. They tend to be stronger during the nighttime and early morning hours and weaker during the day.
It’s always a little creepy when the Santa Ana’s come. You can actually feel the cold air and the hot air blowing at the same time! Legend says that the name originated from the Spanish word Satana, meaning Satan.
My dog freaks out during the Santa Anas. She’s just a little weird during this time. She doesn’t sleep well, and she does little things that are completely out of the ordinary.
Santa Anas can do great damage. The combination of the dry hot air, and our drought right now makes for a very dangerous fire season. These winds also create turbulence and vertical wind shear that causes aviation hazards, and choppy surf conditions.
The Santa Anas only last a few days, but they come wreaking havoc across Southern California once again.
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