The Santa Ana winds are strong, extremely dry offshore winds that characteristically sweep through in Southern California and northern Baja California in late fall and winter. Wind is the flow of Air or other Gases that compose an Atmosphere (including but not limited to the Earth's) Southern California, or So Cal, is defined as the southern portion of the U Baja California (pronounced ˈbɑːhɑː kælɨˈfɔrnjə in English is the northernmost state of Mexico. Temperature-wise, they can range from hot to cold, depending on the prevailing temperatures in the source regions, the Great Basin and upper Mojave Desert. The Great Basin is a large arid region of the western United States. For the indigenous American tribe see Mohave. The Mojave Desert (moʊˈhɑːvi or /məˈhɑːvi/ ( Hayikwiir Mat'aar in Mojave
Santa Anas are a type of drainage wind, an offshore wind that results from the buildup of air pressure in the high-altitude Great Basin between the Sierra Nevada and the Rocky Mountains. A katabatic wind, from the Greek word katabatikos meaning "going downhill" is the technical name for a drainage Wind, a wind High altitude are regions on the Earth 's surface (or in its atmosphere) that are high above Mean sea level. The Great Basin is a large arid region of the western United States. The Sierra Nevada ( Spanish for "Snowy Range" is a Mountain range located in the U Mountain peaks of the Rocky Mountains The Rocky Mountains, often called the Rockies, are a Mountain range in western North America. When upper level winds are favorable, this high altitude air mass spills out of the Great Basin and is propelled gravitationally towards the southern California coastline, generally as a northeasterly wind.
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. For the indigenous American tribe see Mohave. The Mojave Desert (moʊˈhɑːvi or /məˈhɑːvi/ ( Hayikwiir Mat'aar in Mojave The Sonoran Desert (sometimes called the Gila Desert after the Gila River or the Low Desert in opposition to the higher Mojave Desert) is A desert is a Landscape or region that receives very little precipitation. The Santa Ana winds usually form during autumn and early spring when the surface air in the elevated regions of the Great Basin and Mojave Desert (the "high desert") becomes cool or even cold, although they may form at virtually any time of year. The air heats up due to adiabatic heating during its descent. The lapse rate is defined as the negative of the rate of change in an atmospheric variable usually Temperature, with height in an atmosphere While the air has already been dried by orographic lift before reaching the Great Basin as well as by subsidence from the upper atmosphere, the relative humidity of the air is further decreased as it descends from the high desert toward the coast, often falling below 10 percent. Orographic lift occurs when an Air mass is forced from a low Elevation to a higher elevation as it moves over rising terrain
The air from the high desert is initially relatively dense owing to its coolness and aridity, and thus tends to channel down the valleys and canyons in gusts which can attain hurricane force at times. As it descends, the air not only becomes drier, but also warms adiabatically by compression. This article covers adiabatic processes in Thermodynamics. For adiabatic processes in Quantum mechanics, see Adiabatic process (quantum mechanics The southern California coastal region gets some of 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.
The combination of wind, heat, and dryness accompanying the Santa Ana winds turns the chaparral into explosive fuel feeding the infamous wildfires for which the region is known. Chaparral is a Shrubland or heathland Plant community found primarily in the U A wildfire, also known as a wildland fire, forest fire, brush fire, vegetation fire, grass fire, Peat fire, Wildfires fanned by Santa Ana winds burned 721,791 acres (2,921 km²) in two weeks during October 2003.  These same winds have contributed to the fires that have burned some 426,000 acres as of late October 2007. 
Although the winds often have a destructive nature, they have some positive benefits as well. They cause cold water to rise from below the surface layer of the ocean, 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 the upwelling. The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense cooler and usually nutrient-rich water towards the ocean surface replacing the warmer Chlorophyll concentrations in the surface water go from negligible, in the absence of winds, to very active at more than 1. Chlorophyll is a green Pigment found in most Plants Algae and Cyanobacteria. 5 milligrams per cubic meter in the presence of the winds.
A Santa Ana fog is derivative phenomenon in which a ground fog settles in Southern California during the end of a Santa Ana wind episode. Fog is a cloud that is in contact with the ground Stratus clouds are usually the only clouds that touch the ground Southern California, or So Cal, is defined as the southern portion of the U When Santa Ana conditions prevail, with winds in the lower two to three kilometers (1. 25-1. 8 m) of the atmosphere from the north through east, the lower atmosphere continues to be dry. But as soon as the Santa Ana winds cease, the cool and moist marine layer forms rapidly. A marine layer is an air mass which develops over the surface of a large body of water such as the ocean or large lake in the presence of a Temperature inversion. The air in the marine layer becomes very moist and fog occurs. 
A related phenomenon occurs when the Santa Ana condition is present but weak, allowing hot dry air to accumulate in the inland valleys that may not push all the way to sea level. Under these conditions auto commuters can drive from the San Fernando Valley where conditions are sunny and warm, over the low Santa Monica Mountains, to plunge into the cool cloudy air, low clouds, and fog characteristic of the marine air mass. This and the "Santa Ana fog" above constitute examples of an air inversion. In meteorology an inversion is a deviation from the normal change of an atmospheric property with altitude
While characteristically hot and dry, the Santa Anas can also blow cold and dry, and in fact can bring some of Southern California's coldest weather. High cloudiness, most commonly cirrus and altostratus, but also lenticular clouds may be observed, and on rare occasions these usually dry southwest-flowing winds can bring rain. Cirrus clouds are characterized by thin wisplike strands often accompanied by tufts leading to their common (non-standard name of 'mare's tail' Altostratus is a Cloud belonging to a class characterized by a generally uniform gray sheet or layer Lighter in color than nimbostratus and Lenticular clouds are stationary lens-shaped Clouds that form at high altitudes normally aligned at right-angles to the wind direction
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. The Los Angeles Basin is the coastal Sediment -filled plain located between the peninsular and transverse ranges in southern California in In Meteorology, visibility is a measure of the Distance at which an object or light can be clearly discerned
The adverse pulmonary health impacts have been understood by local doctors for decades; the winds pick up and transmit grit, dust, pollens, mold spores and other irritants and allergens for considerable distances.
Residents regularly notice a build-up of dust in their homes and grit on their properties during these periods, which are frequent during the winter.
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. Santa Barbara is a city in Santa Barbara County California, United States. 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, and are strongest at sunset, or "sundown," hence their name. Since high pressure areas usually migrate east, changing the pressure gradient in southern California to the northeast, it is common for "sundowner" wind events to precede Santa Ana events by a day or two. 
Winds blowing off the elevated glaciated plateaus of Greenland and Antarctica experience the most extreme form of katabatic wind, of which the Santa Ana is a type, for the most part. Greenland (Kalaallit Nunaat meaning "Land of the Greenlanders" Grønland is a self-governing Danish Province located between the A katabatic wind, from the Greek word katabatikos meaning "going downhill" is the technical name for a drainage Wind, a wind The winds start at a high elevation and flow outward and downslope, attaining hurricane gusts in valleys, along the shore, and even out to sea. Like the Santa Ana, these winds also heat up by compression and lose humidity, but since they start out so extraordinarily cold and dry and blow over snow and ice all the way to the sea, the perceived difference is negligible.
The winds are also associated with some of the area's largest and deadliest wildfires, including the state's largest fire on record, the Cedar Fire, as well as the Laguna Fire, Old Fire, Esperanza Fire, Santiago Canyon Fire of 1889 and the Witch Fire. A wildfire, also known as a wildland fire, forest fire, brush fire, vegetation fire, grass fire, Peat fire, The Cedar Fire was a human-caused Wildfire which burned out of control through a large area of Southern California in October 2003 The Laguna Fire, previously known as the Kitchen Creek Fire and the Boulder Oaks Fire, was at its time the largest Wildfire in the history of California The Esperanza Fire was a wind-driven Arson -caused Wildfire that started in a river wash near Cabazon California. The Santiago Canyon Fire of 1889 was a Wildfire in California which burned large parts of Orange County and San Diego County during the last
In October 2007 the winds fueled major wild fires and house burnings in Escondido, Malibu, San Marcos, Carlsbad, Rancho Bernardo, Poway, and in the major cities of San Bernardino, San Diego and Los Angeles. Escondido ( "eskun-DEE-doe") is a city located in northern San Diego County California just north of the city of San Diego. Malibu is an incorporated city in western Los Angeles County, California, United States. San Marcos is a city located in the northern portion of San Diego County California, USA. Carlsbad is a seaside resort-town in the North County section of San Diego County California. Rancho Bernardo is a planned community of the city of San Diego California, located in San Diego County Poway (ˈpaʊeɪ is a city in San Diego County, California, United States. Los Angeles (lɑˈsændʒələs los ˈaŋxeles in Spanish) is the largest City in the state of California and the American West
Santa Ana winds may get their name from the Santa Ana Mountains in Orange County, the Santa Ana River or Santa Ana Canyon, along which the winds are particularly strong. The Santa Ana Mountains are a short peninsular Mountain range along the coast of Southern California in the United States. The Santa Ana River begins in San Bernardino County California, in the San Bernardino National Forest. Santa Ana Canyon (or the Santa Ana Narrows) is where the Santa Ana River passes between the Santa Ana Mountains and the Chino Hills at the There are also claims that the original form is Santana winds, from the Spanish vientos de Satán ("winds of Satan", Sanatanas being a rarer form of Satanás), and that this, in turn, is a translation of a native name in some unspecified language. Satan, ( Standard Hebrew Satan'el, English accuser) is a term that originates from the Abrahamic faiths, being traditionally
According to the Los Angeles Almanac: "The original spelling of the name of the winds is unclear, not to mention the origin. The name Santana Winds is said to be traced to Spanish California, when the winds were called devil winds due to their heat. The reference book Los Angeles A to Z (by Leonard & Dale Pitt), credits the Santa Ana Canyon in Orange County as the origin of the name Santa Ana Winds, thereby arguing for the term Santa Anas. This might be supported by early accounts which attributed the Santa Ana Riverbed running through the canyon as the source of the winds. The Santa Ana River begins in San Bernardino County California, in the San Bernardino National Forest. Another account placed the origin of Santa Ana winds with an Associated Press correspondent stationed in Santa Ana who mistakenly began using Santa Ana winds instead of Santana winds in a 1901 dispatch. The Associated Press ( AP) is an American News agency. The AP is a Cooperative owned by its contributing Newspapers radio "
|“||Those 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.||”|
—Raymond Chandler, "Red Wind"