As the wind-whipped fires continues to threaten Southern California, San Luis Obispo County isn’t seeing nearly the types of ferocious winds that can turn a basic brush fire into an inferno.
That’s due to a few factors, said PG&E meteorologist John Lindsey.
One of those factors is the topography of the state. The feared Santa Ana winds begin from a position of high pressure in Nevada’s Great Basin before blowing toward California, Lindsey said.
To reach Southern California, those winds blow over the Mojave desert, where they’re heated further and pushed to higher speeds as they blow down into the Ventura and Los Angeles county areas, Lindsey said.
Thanks to its location farther to the north, SLO County is out of the winds’ path.
“Those winds are coming from Nevada, and the Sierra Nevada acts as block,” Lindsey said. “It forces the winds south toward the Mojave Desert, where they careen down the mountains toward Ventura and Los Angeles.”
And the mountains in the Ventura and Los Angeles areas are much higher in elevation than the ones in San Luis Obispo County.
For comparison, the Cuesta Grade is just over 1,500 feet in elevation, while the San Gabriel Mountains outside Los Angeles are much taller — the highest point in that mountain range is Mt. San Antonio, just over 10,000 feet in elevation.
“It’s a natural funnel, and then the winds are starting out at a much higher altitude than they are in San Luis,” Lindsey said.
SLO County does see its own type of Santa Ana winds — known as the Santa Lucias — and Lindsey said there have been credible reports of gusts up to 80 mph by the TV towers on top of the Cuesta Grade.
The county also does have natural funnels of its own, notably the Highway 41 corridor between Atascadero and Morro Bay, but the winds that blow through there “tend not to be as strong as the Santa Anas,” Lindsey said.