Sierra Azul

{{Short description|Mountain range in the state of California}}

{{Infobox mountain

| name = Sierra Azul

| native_name =

| other_name =

| etymology =

| photo = Umunhum.JPG

| photo_caption = Mt Umunhum is the highest point of the Sierra Azul

| country = United States

| state = California

| region =

| district = Santa Clara County

| topo_map = Los Gatos

| topo_maker = USGS

| border =

| parent = Santa Cruz Mountains

| range_coordinates = {{coord|37|10|6.804|N|121|54|41.841|W|type:mountain_scale:300000|format=dms|display=inline,title}}

| highest =

| elevation_m = 883

| coordinates =

| length_mi = | length_orientation =

| width_mi = | width_orientation =

| area_mi2 =

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| map = California

| map_caption = location of Sierra Azul in California{{cite gnis|id=253850|name=Sierra Azul|accessdate=2009-05-04}}

}}

The Sierra Azul is a mountain range in Santa Clara County, California. It is the southern half of the Santa Cruz Mountains range, which is divided into two parts by California Highway 17 into what the colonizing Spanish called the Sierra Morena or "Brown Mountains" to the north and the Sierra Azul or "Blue Mountains" to the south.{{cite book |title=California Place Names: The Origin and Etymology of Current Geographical Names |author=Erwin Gustav Gudde |page=[https://archive.org/details/1000californiapl00guddrich/page/18 18] |url=https://archive.org/details/1000californiapl00guddrich |url-access=registration |quote=gudde place names sierra azul. |accessdate=2014-07-26 |publisher=University of California Press |year=1960 }}{{cite book |title=Flora of the Santa Cruz Mountains of California: A Manual of the Vascular Plants |author=John Hunter Thomas |page=5 |year=1991 |publisher=Stanford University Press |isbn=978-0-8047-1862-2 |url=https://books.google.com/books?id=jTh8OF-Y9SwC&dq=%22sierra+morena%22+%22santa+cruz+county%22&pg=PA3 |accessdate=2014-07-26 }}{{cite book |title=A memorial and biographical history of the coast counties of Central California |author=Luther A. Ingersoll |editor=Henry D. Barrows |year=1893 |publisher=Lewis Publishing Company |page=[https://archive.org/details/bub_gb_nxUVAAAAYAAJ/page/n195 190] |url=https://archive.org/details/bub_gb_nxUVAAAAYAAJ |quote=sierra morena san mateo county. |accessdate=2014-07-26 }} Part of the range is within the Sierra Azul Open Space Preserve.

The highest peak is Mount Umunhum, the site of the former Almaden Air Force Station radar site and the current location of a NEXRAD weather radar of the National Weather Service which serves the San Francisco Bay Area and Monterey Bay Area.