Editing Sierra Nevada (section)

==Climate and meteorology==
[[File:Red Slate Mountain 1.jpg|thumb|[[Red Slate Mountain]] (elevation {{cvt|13156|ft|m|disp=or}}) is still covered with snow in June]]<!-- An example of how the snowpack in the Sierra lasts until June -->

The climate of the Sierra Nevada is influenced by the [[Mediterranean climate]] of California. During the fall, winter and spring, precipitation in the Sierra ranges from {{cvt|20|to|80|in|mm}} where it occurs mostly as snow above {{cvt|6000|ft|m}}. Precipitation is highest on the central and northern portions of the western slope between {{convert|5000|and|8000|ft|m}} elevation, due to [[orographic lift]].<ref name="Schoenherr" />{{rp|69}} Above {{convert|8000|ft|m}}, precipitation diminishes on the western slope up to the crest, since most of the precipitation has been wrung out at lower elevations. Most parts of the range east of the crest are in a [[rain shadow]], and receive less than 25 inches of precipitation per year.<ref>{{cite web |url=http://www.sierranevadaphotos.com/geography/sierra_precipitation.asp |title=Average Annual Precipitation |publisher=Sierra Nevada Photos |access-date=January 2, 2014 |archive-url=https://web.archive.org/web/20080222205344/http://www.sierranevadaphotos.com/geography/sierra_precipitation.asp |archive-date=February 22, 2008 |url-status=dead}}</ref> While most summer days are dry, afternoon thunderstorms are common, particularly during the [[North American Monsoon]] in mid and late summer. Some of these summer thunderstorms drop over an inch of rain in a short period, and the lightning can start fires. Summer high temperatures average {{cvt|42|-|90|F|C}}. Winters are comparatively mild, and the temperature is usually only just low enough to sustain a heavy snowpack. For example, [[Tuolumne Meadows]], at {{convert|8600|ft|m}} elevation, has winter daily highs about {{cvt|40|F|C}} with daily lows about {{cvt|10|F|C}}.<ref>{{cite web |url=https://www.nps.gov/yose/planyourvisit/weather.htm |title=Weather |work=Yosemite |publisher=National Park Service |access-date=October 8, 2016 |archive-date=October 9, 2016 |archive-url=https://web.archive.org/web/20161009152047/https://www.nps.gov/yose/planyourvisit/weather.htm |url-status=live }}</ref> The growing season lasts 20 to 230 days, strongly dependent on elevation.<ref name="ecosubregions" /> The highest elevations of the Sierra have an [[alpine climate]].

The Sierra Nevada snowpack is the major source of water and a significant source of electric power generation in California.<ref>{{cite web |url=http://www.sierranevada.ca.gov/docs/Water09.pdf |archive-url=https://web.archive.org/web/20100618010332/http://www.sierranevada.ca.gov/docs/Water09.pdf |archive-date=June 18, 2010 |title=Water—Most of California's Water Comes from the Sierra Nevada |publisher=Sierra Nevada Conservancy |access-date=June 9, 2010 |url-status=dead}}</ref> Many reservoirs were constructed in the canyons of the Sierra throughout the 20th century, Several major aqueducts serving both agriculture and urban areas distribute Sierra water throughout the state. However, the Sierra casts a [[rain shadow]], which greatly affects the climate and ecology of the central [[Great Basin]]. This rain shadow is largely responsible for Nevada being the driest state in the United States.<ref>{{cite web |url=http://www.esrl.noaa.gov/psd/data/usclimate/pcp.state.19712000.climo |title=Climatology by state based on climate division data: 1971–2000 |publisher=NOAA Earth Systems Research Laboratory |access-date=July 11, 2010 |archive-date=April 21, 2013 |archive-url=https://web.archive.org/web/20130421024731/http://www.esrl.noaa.gov/psd/data/usclimate/pcp.state.19712000.climo |url-status=live }}</ref>

Precipitation varies substantially from year to year. It is not uncommon for some years to receive precipitation totals far above or below normal.

The height of the range and the steepness of the Sierra Escarpment, particularly at the southern end of the range, produces a wind phenomenon known as the "Sierra Rotor". This is a horizontal rotation of the atmosphere just east of the crest of the Sierra, set in motion as an effect of strong westerly winds.<ref>{{cite conference |url=http://ams.confex.com/ams/pdfpapers/114663.pdf |publisher=American Meteorological Society |conference=12th Conference on Mountain Meteorology |title=Sierra Rotors: A Comparative Study of Three Mountain Wave and Rotor Events |first1=Vanda |last1=Grubišic |first2=Brian J. |last2=Billings |date=2006 |access-date=May 8, 2010 |archive-date=July 5, 2011 |archive-url=https://web.archive.org/web/20110705015959/http://ams.confex.com/ams/pdfpapers/114663.pdf |url-status=live }}</ref>

The Sierra Nevada is home to the [[Mono winds]], strong, dry downslope winds that primarily affect the western slopes, especially in the central region, and are most common from late fall to spring. With gusts reaching over 80 miles per hour, these winds can cause widespread disruption, uprooting trees, damaging infrastructure, and making mountain passes hazardous for drivers.<ref>{{cite journal | last1=Ruscha | first1=Charles P. Jr. |date=February 1976 |title=Forecasting the Mono Wind |url=https://www.weather.gov/media/wrh/online_publications/TMs/TM-105.pdf |journal=National Oceanic and Atmospheric Administration |volume=NWS WR-105 |issue= |pages= |doi= |access-date=November 22, 2021}}</ref>

{{anchor|Nevada Triangle}}
Because of the large number of airplanes that have crashed in the Sierra Nevada, primarily due to the complex weather and atmospheric conditions such as [[downdrafts]] and [[microbursts]] caused by geography there, a portion of the area, a triangle whose vertices are [[Reno, Nevada]]; [[Fresno, California]]; and [[Las Vegas, Nevada]], has been dubbed the "'''Nevada Triangle'''", in reference to the [[Bermuda Triangle]]. Some counts put the number of crashes in the triangle at 2,000,<ref>{{cite web |last1=Schoenmann |first1=Joe |title=The Nevada Triangle: A Graveyard For Planes |url=https://knpr.org/knpr/2015-09/nevada-triangle-graveyard-planes |website=knpr.org |access-date=March 18, 2019 |archive-date=March 2, 2019 |archive-url=https://web.archive.org/web/20190302034650/https://knpr.org/knpr/2015-09/nevada-triangle-graveyard-planes |url-status=live }}</ref> including millionaire and record-breaking flyer [[Steve Fossett]]. Hypotheses that the crashes are related in some way to the [[United States Air Force]]'s [[Area 51]], or to the activities of [[extra-terrestrial aliens]], have no evidence to support them.<ref>{{cite news |last=Winter |first=Stuart |url=http://www.express.co.uk/news/world/149355/Mystery-of-the-Nevada-Triangle |title=Mystery of the Nevada Triangle |newspaper=[[Sunday Express]] |date=January 3, 2010 |access-date=September 15, 2015 |archive-date=August 20, 2015 |archive-url=https://web.archive.org/web/20150820000256/http://www.express.co.uk/news/world/149355/Mystery-of-the-Nevada-Triangle |url-status=live }}</ref><ref>{{cite AV media |people=Pupp, Martin (director) |url=http://www.smithsonianchannel.com/shows/the-missing-evidence/the-nevada-triangle/1003747/3418206 |title=The Missing Evidence: Nevada Triangle |format=TV series episode |date=December 1, 2014 |access-date=September 15, 2015 |archive-date=September 2, 2015 |archive-url=https://web.archive.org/web/20150902211613/http://www.smithsonianchannel.com/shows/the-missing-evidence/the-nevada-triangle/1003747/3418206 |url-status=live }}</ref>