Santa Ana wind

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Smoke from the October 2003 fires blowing out to sea.

This article is about a meteorological phenomenon. For information about the Orange County, California woodwind group see: The Santa Ana Winds Youth Band

The Santa Ana winds are warm, dry winds that characteristically appear in Southern California weather during autumn and early winter.

1 Meteorology
2 Nomenclature
3 Santa Ana winds in popular culture
4 See also
5 References

[edit] Meteorology

QuikSCAT image showing the speed of the Santa Ana winds (m/s).

Santa Anas are a type of föhn wind, the result of air pressure buildup in the high-altitude Great Basin between the Sierra Nevada and the Rocky Mountains. This air mass spills out of the Great Basin and is pulled by gravity into the surrounding lowlands. The air circulates clockwise around the high pressure area bringing winds from the east and northeast to Southern California (the reverse of the westerly winds characteristic of the latitude).

It is often said that the air is heated and dried as it passes through the Mojave and Sonoran Deserts, but according to meteorologists this is a popular misconception. The Santa Ana winds actually form during autumn and early spring when the desert is relatively cold. The air heats up due to adiabatic heating while being compressed during its descent. While the air has already been dried by orographic lift prior to reaching the Great Basin, the relative humidity of the air declines rapidly as it descends and warms in its final stages as it passes over the Transverse and Peninsular Ranges.

The air is then forced down the mountain slopes out towards the Pacific coast; the air mass is further heated by compression as it drops in altitude before reaching the Los Angeles Basin and western San Diego County at typical speeds of 35 knots. The southern California coastal region gets its hottest weather of the year during autumn while Santa Ana winds are blowing. During Santa Ana conditions it is typically hotter along the coast than in the deserts and the humidity plummets to less than 15%.

As the Santa Ana winds are channeled through the mountain passes they can approach hurricane force. The combination of wind, heat, and dryness turns the chaparral into explosive fuel for the infamous wildfires the region is known for. Wildfires fanned by Santa Ana winds burned 721,791 acres (2,921 km²) in two weeks during October 2003.

Although the winds often have a destructive nature, they have some positive benefits as well. They cause cold water to rise from the bottom of the ocean to the top, bringing with it many nutrients that ultimately benefit local fisheries. As the winds blow over the ocean, sea surface temperatures drop about 4 °C (7 °F), indicating an upwelling of deep ocean water. Chlorophyll concentrations in the surface water go from negligible, in the absence of winds, to very active at more than 1.5 milligrams per cubic meter in the presence of the winds.

To the north, in the Santa Barbara area, the Santa Ana winds are weaker and are usually held at bay by topography: the local mountains offer no prominent outlets, in the form of passes or river valleys, from the elevated inland source areas. However, a variant of the Santa Ana wind, known locally as Sundowner winds, often invade the area. These are downslope winds which occur when a high pressure area lies due north of Santa Barbara, and occur most frequently in the late spring to early summer. The hottest temperature ever recorded in North America outside Death Valley, 133 °F (56 °C), was unoffically recorded on June 17, 1859 off the coast of Santa Barbara during a Sundowner wind. However, weather instruments during that period were unreliable and the actual temperature was closer to 109 °F (43 °C), the highest official reading. Most meteorologists do not recognize the historical record.

In the Brookings and Gold Beach areas along the southern Oregon coast they are called the Brookings Effect (or Chetco effect); and in the northern Plains such winds off the Rocky Mountains are called Chinook winds.

In the Los Angeles Basin, the winds are often credited with the extremely high visibility experienced in the area during the winter, in contrast to the hazy, smoggy summers.

[edit] Nomenclature

Santa Ana winds may get their name from the Santa Ana Mountains that lie in Orange County or the Santa Ana Canyon through which the winds are noted for their high speed. Many Southern Californians believe that the traditional name is Santanas, meaning devil winds in an undetermined language. The similar word "Satanás" is Spanish for "Satan." Santanas was occasionally used in early reports, but modern scholars have not agreed on the etymology of the word. It is rarely spelled that way today, though the pronunciation is still heard.

[edit] Santa Ana winds in popular culture

The Santa Ana winds are referenced in the Raymond Chandler short story "Red Wind," in which the author describes the winds as such: "[T]hose hot dry [winds] that come down through the mountain passes and curl your hair and make your nerves jump and your skin itch. On nights like that every booze party ends in a fight. Meek little wives feel the edge of the carving knife and study their husbands' necks. Anything can happen." Appropriately, this Chandler passage is read by Chris Stevens (John Corbett) at the beginning of the episode "Ill Wind" of the TV series Northern Exposure. This passage is also quoted by Ed Asner in his role as Lou Grant in "The Mary Tyler Moore Show" as an example of how to write prose.
Bad Religion mentions the winds, using their nickname "murder winds," in the song "Los Angeles Is Burning" from the album Empire Strikes First. "When the hills of Los Angeles are burning/ Palm trees are candles in the murder winds/ So many lives are on the breeze/ Even the stars are ill at ease/ And Los Angeles is burning."
There is also a band named The Santa Ana Winds Youth Band.
There is a reference made to the winds in the Steely Dan song, "Babylon Sisters"
The Beach Boys song "Santa Ana Winds" appears on their 1980 album Keepin' the Summer Alive.
The song LA Woman by the Doors references taking a look around "see which way the wind blows" and contains imagery in which the city's "hair is burnin’ hills are filled with fire."
The song Summer Rain by Belinda Carlisle has the lyrics "I remember the rain on our skin. And his kisses hotter than the Santa Ana Winds."
The Santa Ana winds are important to the plot of the book White Oleander by Janet Fitch.
The song "Catch My Disease" by Ben Lee has the lyrics "She told me about the winds from Santa Ana/And thats the way I like it."
The Winds were featured prominently in the October 22, 2006 episode of the ABC series "Brothers & Sisters."
The Santa Ana Winds are referred to in the song "I love L.A" by Randy Newmann Lyrics: " And the Santa Ana Winds blowing hot from the north"
Rancid makes reference to the winds in the song "Brad" on the South Park Chef Aid album. "...and the Santa Ana winds make me feel alright."
Several references made in the hit TV show Beverly Hills, 90210