This week’s dire weather forecasts, and public safety warnings, are filled with some unfamiliar terms and abbreviations. Here are a few and what they mean, per the National Weather Service, UCLA and the Sierra Club.
Santa Ana winds: Dry, downslope winds from the north, northeast or east that blow from the desert toward the sea in Southern California, usually from October to March.
The winds are often warm up and sometimes turn hot — but not always. The current Santa Ana event is cold, because it drew lots of cold air from Canada. Southern California ski resorts may easily be able to make snow over the next few days.
The Santa Anas range from weak to extreme in power. In the past, the winds have gusted more than 90 mph in San Diego County’s Cuyamaca Mountains.
Mountain waves: The current wind event originated in the Nevada and Utah regions of the Great Basin, where high pressure produced winds that are flowing into Southern California.
That’s leading to the creation of mountain waves, which arise when strong winds blow perpendicular to a mountain range. The waves shoot down the coastal side of the mountains, gaining speed along the way, and are more casually referred to as simple Santa Ana winds.
High wind warning: Such a warning is issued when forecasters expect either sustained winds of 40 mph for at least an hour, or gusts of 58 mph or more.
A high wind watch, on the other hand, is issued when winds are expected to be weaker but gusty.
