Editing Los Angeles (section)

===Climate===
{{Main|Climate of Los Angeles}}

{{climate chart
| Los Angeles (Downtown)
|48.9|68.0|3.29
|50.0|68.0|3.64
|52.4|69.9|2.23
|54.8|72.4|0.69
|58.1|73.7|0.32
|61.4|77.2|0.09
|64.7|82.0|0.02
|65.4|84.0|0.00
|64.2|83.0|0.13
|59.9|78.6|0.58
|53.1|72.9|0.78
|48.2|67.4|2.48
|float     = right
|clear     = right
|units     = imperial
|source    = NOAA<ref name="Los Angeles Downtown Weatherbox NOAA txt"/>}}
Los Angeles has a two-season [[semi-arid climate]] ([[Köppen climate classification|Köppen]]: ''BSh'') with dry summers and very mild winters, but it receives more annual precipitation than most semi-arid climates, narrowly missing the boundary of a Mediterranean climate ([[Köppen climate classification|Köppen]]: ''Csb'' on the coast, ''Csa'' otherwise).<ref name="Peel">{{cite journal|author1=Peel, M. C.|author2=Finlayson B. L.|author3=McMahon, T. A.|name-list-style=amp|year=2007|title=Updated world map of the Köppen−Geiger climate classification |bibcode-access=free |journal=Hydrol. Earth Syst. Sci.|volume=11|issue=5|pages=1633–1644|doi=10.5194/hess-11-1633-2007|issn=1027-5606|doi-access=free|bibcode=2007HESS...11.1633P}}</ref> Daytime temperatures are generally temperate all year round. In winter, they average around {{convert|68|F}}.<ref>{{cite web|url=https://boomcalifornia.com/2017/05/22/the-myth-of-a-desert-metropolis-los-angeles-was-not-built-in-a-desert-but-are-we-making-it-one/ |first1=Glen M. |last1=MacDonald |title=The Myth of a Desert Metropolis: Los Angeles was not built in a desert, but are we making it one?|date=May 22, 2017|website=Boom California|language=en|access-date=March 8, 2019|archive-date=March 8, 2019|archive-url=https://web.archive.org/web/20190308110817/https://boomcalifornia.com/2017/05/22/the-myth-of-a-desert-metropolis-los-angeles-was-not-built-in-a-desert-but-are-we-making-it-one/|url-status=live}}</ref> Autumn months tend to be hot, with major heat waves a common occurrence in September and October, while the spring months tend to be cooler and experience more precipitation. Los Angeles has plenty of sunshine throughout the year, with an average of only 35 days with measurable precipitation annually.<ref name="weatherbase">{{cite web|url=http://www.weatherbase.com/weather/weather.php3?s=159227&refer=|title=Historical Weather for Los Angeles, California, United States of America|publisher=Weatherbase|access-date=December 15, 2011|archive-date=January 11, 2012|archive-url=https://web.archive.org/web/20120111084326/http://www.weatherbase.com/weather/weather.php3?s=159227&refer=|url-status=live}}</ref>

Temperatures in the coastal basin exceed {{convert|90|F}} on a dozen or so days in the year, from one day a month in April, May, June and November to three days a month in July, August, October and to five days in September.<ref name="weatherbase" /> Temperatures in the San Fernando and San Gabriel Valleys are considerably warmer. Temperatures are subject to substantial daily swings; in inland areas the difference between the average daily low and the average daily high is over {{convert|30|F-change|0}}.<ref name="NCDC-CANOGA">{{cite web|url=http://cdo.ncdc.noaa.gov/climatenormals/clim20/ca/041484.pdf|title=Climatography of the United States No. 20 (1971–2000)|year=2004|publisher=[[National Oceanic and Atmospheric Administration]]|archive-url=https://web.archive.org/web/20130902181245/http://cdo.ncdc.noaa.gov/climatenormals/clim20/ca/041484.pdf|archive-date=September 2, 2013|url-status=dead|access-date=October 5, 2011}}</ref> The average annual temperature of the sea is {{convert|63|F}}, from {{convert|58|F}} in January to {{convert|68|F}} in August.<ref>{{cite web|url=http://www.beachcalifornia.com/beach/california-ocean-temperature.html|title=Pacific Ocean Temperatures on California Coast|publisher=beachcalifornia.com|access-date=October 5, 2011|archive-date=October 12, 2011|archive-url=https://web.archive.org/web/20111012162654/http://www.beachcalifornia.com/beach/california-ocean-temperature.html|url-status=live}}</ref> Hours of sunshine total more than 3,000 per year, from an average of 7 hours of sunshine per day in December to an average of 12 in July.<ref>{{cite web|url=http://www.weather2travel.com/climate-guides/united-states/california/los-angeles-ca.php|title=Los Angeles Climate Guide|publisher=weather2travel.com|access-date=October 5, 2011|archive-date=October 5, 2011|archive-url=https://web.archive.org/web/20111005120119/http://www.weather2travel.com/climate-guides/united-states/california/los-angeles-ca.php|url-status=live}}</ref>

Due to the mountainous terrain of the surrounding region, the Los Angeles area contains a large number of distinct [[microclimate]]s, causing extreme variations in temperature in close physical proximity to each other. For example, the average July maximum temperature at the [[Santa Monica Pier]] is {{convert|70|F}} whereas it is {{convert|95|F}} in Canoga Park, {{convert|15|mi}} away.<ref name="climateofCA">{{cite web|url=http://www.wrcc.dri.edu/narratives/CALIFORNIA.htm|title=Climate of California|publisher=Western Regional Climate Center|access-date=October 6, 2011|archive-date=July 21, 2009|archive-url=https://web.archive.org/web/20090721042030/http://www.wrcc.dri.edu/narratives/CALIFORNIA.htm|url-status=dead}}</ref> The city, like much of the Southern Californian coast, is subject to a late spring/early summer weather phenomenon called "[[June Gloom]]". This involves overcast or foggy skies in the morning that yield to sun by early afternoon.<ref name="Poole2010">{{cite book|url=https://books.google.com/books?id=HAPWv2OkeXUC&pg=PA22|title=Frommer's Los Angeles 2011|last=Poole|first=Matthew R.|date=September 22, 2010|publisher=John Wiley & Sons|isbn=978-0-470-62619-1|page=22|access-date=October 5, 2011|archive-date=November 6, 2023|archive-url=https://web.archive.org/web/20231106164902/https://books.google.com/books?id=HAPWv2OkeXUC&pg=PA22|url-status=live}}</ref>
[[File:Lake Hollywood Reservoir by clinton steeds.jpg|thumb|left|[[Hollywood Reservoir|Lake Hollywood]] in the [[Santa Monica Mountains]]]]
More recently, statewide [[droughts in California]] have further strained the city's [[water security]].<ref name="drought continues">{{Cite web |last=Smith |first=Hayley |date=March 1, 2022 |title=California drought continues after state has its driest January and February on record |url=https://www.latimes.com/california/story/2022-03-01/california-drought-will-continue-after-dry-winter |url-status=live |archive-url=https://web.archive.org/web/20220309150823/https://www.latimes.com/california/story/2022-03-01/california-drought-will-continue-after-dry-winter |archive-date=March 9, 2022 |access-date=November 23, 2022 |website=[[Los Angeles Times]] |language=en-US}}</ref> Downtown Los Angeles averages {{convert|14.67|in|mm|abbr=on}} of precipitation annually, mainly occurring between November and March,<ref>{{cite web | url=http://www.laalmanac.com/weather/we13.php | title=Los Angeles Almanac – seasonal average rainfall | accessdate=December 26, 2021 | archive-date=December 27, 2021 | archive-url=https://web.archive.org/web/20211227074311/http://www.laalmanac.com/weather/we13.php | url-status=live }}</ref><ref name="NCDC-CANOGA" /> generally in the form of moderate rain showers, but sometimes as heavy rainfall during winter storms. Rainfall is usually higher in the hills and coastal slopes of the mountains because of [[orographic]] uplift. Summer days are usually rainless. Rarely, an incursion of moist air from the south or east can bring brief thunderstorms in late summer, especially to the mountains. The coast gets slightly less rainfall, while the inland and mountain areas get considerably more. Years of average rainfall are rare. The usual pattern is a year-to-year variability, with a short string of dry years of {{convert|5|–|10|in|abbr=on|mm}} rainfall, followed by one or two wet years with more than {{convert|20|in|mm|abbr=on}}.<ref name="NCDC-CANOGA" /> Wet years are usually associated with warm water [[El Niño]] conditions in the Pacific, dry years with cooler water [[La Niña]] episodes. A series of rainy days can bring floods to the lowlands and mudslides to the hills, especially after [[wildfire]]s have denuded the slopes.
[[File:Venice Beach, Los Angeles, CA 07.JPG|thumb|right|[[Venice, Los Angeles|Venice Beach]] on the [[South Coast (California)|South Coast of California]]]]
Both freezing temperatures and snowfall are extremely rare in the city basin and along the coast, with the last occurrence of a {{convert|32|F}} reading at the downtown station being January 29, 1979;<ref name="NCDC-CANOGA" /> freezing temperatures occur nearly every year in valley locations while the mountains within city limits typically receive snowfall every winter. The greatest snowfall recorded in downtown Los Angeles was {{convert|2.0|in|cm|0}} on January 15, 1932.<ref name="NCDC-CANOGA" /><ref name="BurtStroud2007">{{cite book|url=https://books.google.com/books?id=SV229set7RIC&pg=PA100|title=Extreme weather: a guide & record book|last1=Burt|first1=Christopher C.|last2=Stroud|first2=Mark|date=June 26, 2007|publisher=W. W. Norton & Company|isbn=978-0-393-33015-1|page=100|access-date=October 5, 2011|archive-date=November 6, 2023|archive-url=https://web.archive.org/web/20231106164902/https://books.google.com/books?id=SV229set7RIC&pg=PA100#v=onepage&q&f=false|url-status=live}}</ref> While the most recent snowfall occurred in February 2019, the first snowfall since 1962,<ref>{{cite web|url=https://thehill.com/policy/energy-environment/e2-wire/431056-city-of-los-angeles-sees-first-snow-since-1962|title=Los Angeles sees first snow in years|website=[[The Hill (newspaper)|The Hill]]|last=Frazin|first=Rachel|date=February 21, 2019|publisher=Capitol Hill Publishing Corp.|access-date=April 6, 2019|archive-date=February 23, 2019|archive-url=https://web.archive.org/web/20190223020408/https://thehill.com/policy/energy-environment/e2-wire/431056-city-of-los-angeles-sees-first-snow-since-1962|url-status=live}}</ref><ref>{{cite web|url=https://www.nbcnews.com/video/snow-falling-in-los-angeles-pasadena-and-california-s-coastal-cities-1446644291928|title=Snow falling in Los Angeles, Pasadena and California's coastal cities|website=nbcnews.com|date=February 22, 2019|publisher=NBC Universal|access-date=April 6, 2019|archive-date=April 2, 2019|archive-url=https://web.archive.org/web/20190402012137/https://www.nbcnews.com/video/snow-falling-in-los-angeles-pasadena-and-california-s-coastal-cities-1446644291928|url-status=live}}</ref> with snow falling in areas adjacent to Los Angeles as recently as January 2021.<ref>{{cite web|url=https://www.9news.com/article/weather/accuweather/malibu-snow-snowfall-photos-weather-forecast/507-c4f6e6a1-ce70-4153-859c-273beb266ad7|title=Snow in Malibu? Weather provides surprise in Southern California|website=KUSA.com|date=January 25, 2021|access-date=January 28, 2021|archive-date=May 9, 2022|archive-url=https://web.archive.org/web/20220509050503/https://www.9news.com/article/weather/accuweather/malibu-snow-snowfall-photos-weather-forecast/507-c4f6e6a1-ce70-4153-859c-273beb266ad7|url-status=live}}</ref> Brief, localized instances of hail can occur on rare occasions, but are more common than snowfall. At the official downtown station, the highest recorded temperature is {{convert|113|F}} on September 27, 2010,<ref name="NCDC-CANOGA" /><ref name="RecordHighTemp113">{{cite news|url=https://www.latimes.com/archives/la-xpm-2010-sep-27-la-me-hottest-ever-20100928-story.html|title=L.A.'s hottest day ever|last1=Pool|first1=Bob|date=September 27, 2010|newspaper=[[Los Angeles Times]]|access-date=October 5, 2011|last2=Lin II|first2=Rong-Gong|archive-date=December 13, 2011|archive-url=https://web.archive.org/web/20111213215200/http://articles.latimes.com/2010/sep/27/local/la-me-hottest-ever-20100928|url-status=live}}</ref> while the lowest is {{convert|28|F}},<ref name="NCDC-CANOGA" /> on January 4, 1949.<ref name="NCDC-CANOGA" /> Within the City of Los Angeles, the highest temperature ever officially recorded is {{convert|121|F}}, on September 6, 2020, at the weather station at [[Los Angeles Pierce College|Pierce College]] in the [[San Fernando Valley]] neighborhood of [[Woodland Hills, Los Angeles|Woodland Hills]].<ref>{{cite web |author1=National Oceanic and Atmospheric Administration |title=Los Angeles/Oxnard |url=https://w2.weather.gov/climate/index.php?wfo=lox |website=National Weather Service Forecast Office |access-date=September 9, 2020 |archive-date=September 18, 2020 |archive-url=https://web.archive.org/web/20200918014102/https://w2.weather.gov/climate/index.php?wfo=lox |url-status=live }}</ref> During autumn and winter, [[Santa Ana winds]] sometimes bring much warmer and drier conditions to Los Angeles, and raise wildfire risk.
{{Los Angeles weatherbox}}