It’s the right time of year for Santa Ana winds, and indeed Thursday in the San Fernando Valley warm gusts rattled windows, downed tree limbs and scattered garbage.
But those winds were not Santa Anas.
“It may have felt like a Santa Ana wind, but the atmospheric conditions for a classic Santa Ana were not present,” said meteorologist Jeff House of WeatherData, which provides weather information to The Times.
For “classic” Santa Ana winds, two conditions must be present: A high pressure system over the Great Basin--eastern California, Nevada and western Utah--and a strong jet stream flow out of the northwest. On Thursday, the high pressure system was in place, but the upper atmosphere jet stream was not.
“We didn’t have the upper atmosphere activity needed for even a weak Santa Ana condition,” said weather specialist Stuart Seto of the National Weather Service office in Oxnard.
The last several months have been notable for their scarcity of Santa Anas, which usually scour the area during the fall and early winter.
“Many times, you would get one of the conditions needed for Santa Anas, but not the other,” House said. “They were almost never lining up right.”
The only major Santa Ana winds in recent months arrived during the first week of October and were short-lived.
While Thursday’s warm, dry winds may have not made the classic grade, they did provide pleasant temperatures throughout the area: Burbank had a high of 76, Chatsworth reached 79, Glendale hit 75 and both Northridge and Woodland Hills recorded a 74.
The forecast for Friday calls for continued windy conditions. “But the winds won’t be quite as strong,” Bruce Rockwell of the weather service said. Temperatures are expected to dip only slightly.
On Saturday, temperatures are again expected to reach into the mid-70s to upper 70s, with the winds calm. “It should be very nice,” House said. “The warmth without the winds.”