Editing Flagstaff, Arizona (section)

===Climate===
[[File:Arizona Köppen.svg|thumb|Köppen map of Arizona ([[Oregon State University]], 2016)|alt=See caption]]

Flagstaff's climate type on the [[Köppen climate classification]] system is variously reported as a [[Mediterranean climate#Warm-summer Mediterranean climate|warm dry-summer Mediterranean climate]] (''Csb''),<ref name=":27">{{Cite web|url=http://www.weatherbase.com/weather/weather-summary.php3?s=557327&cityname=Flagstaff,+Arizona,+United+States+of+America|title=Flagstaff, Arizona Köppen Climate Classification (Weatherbase)|website=Weatherbase|access-date=April 9, 2020|archive-date=December 2, 2020|archive-url=https://web.archive.org/web/20201202154407/http://www.weatherbase.com/weather/weather-summary.php3?s=557327&cityname=Flagstaff,+Arizona,+United+States+of+America|url-status=live}}</ref><ref name=":28">{{Cite journal |last1=Chase|first1=John|last2=Fouquier|first2=Jennifer|last3=Zare|first3=Mahnaz|last4=Sonderegger|first4=Derek L.|last5=Knight|first5=Rob|last6=Kelley|first6=Scott T.|last7=Siegel|first7=Jeffrey|last8=Caporaso|first8=J. Gregory|date=April 26, 2016|editor-last=Gilbert|editor-first=Jack A.|title=Geography and Location Are the Primary Drivers of Office Microbiome Composition|journal=mSystems|language=en|volume=1|issue=2|pages=e00022–16, /msys/1/2/e00022–16.atom|doi=10.1128/mSystems.00022-16|issn=2379-5077|pmc=5069741|pmid=27822521}}</ref> a [[Humid continental climate#Warm summer subtype|Hemiboreal climate]] (''Dsb''<ref name=":28" /> and ''Dfb''<ref>{{Cite web|url=https://www.weather-us.com/en/arizona-usa-climate|title=Arizona, USA – Climate data and average monthly weather|website=Weather Atlas|publisher=Yu Media Group|language=en|access-date=April 9, 2020|archive-date=September 17, 2020|archive-url=https://web.archive.org/web/20200917051628/https://www.weather-us.com/en/arizona-usa-climate|url-status=live}}</ref>), and a [[Semi-arid climate#Cold semi-arid climates|cold semi-arid climate]] (''BSk'').<ref>{{Cite web|url=https://www.skybrary.aero/index.php/KFLG|title=Flagstaff Pulliam Airport – SKYbrary Aviation Safety|website=www.skybrary.aero|access-date=April 9, 2020|archive-date=July 19, 2021|archive-url=https://web.archive.org/web/20210719014427/https://www.skybrary.aero/index.php/KFLG|url-status=live}}</ref><ref>{{Cite journal|last=Newnham|first=E. V.|date=1933|title=Meteorology |journal=Science Progress (1933- )|volume=28|issue=110|pages=284–286|jstor=43410836|issn=0036-8504}}</ref> It is consistently described as "semi-arid".<ref name=":28" /><ref name=":30">{{Cite thesis |last=Weeks |first=Michael A. |date=May 2007 |title=Constructing winter: Flagstaff and the culture of snow, 1937–1990 |type=MA thesis |publisher=Northern Arizona University |url=https://www.researchgate.net/publication/34174171 |access-date=April 10, 2020 |archive-date=July 19, 2021|archive-url=https://web.archive.org/web/20210719014515/https://www.researchgate.net/publication/34174171_Constructing_winter_Flagstaff_and_the_culture_of_snow_1937-1990 |url-status=live |oclc=156878877}}</ref> Flagstaff's Köppen type is recorded as ''Dsb'' in the city center, with areas of ''BSk'', ''Csb'', ''Csa'' ([[Mediterranean climate#Hot-summer Mediterranean climate|hot-summer Mediterranean]]), ''Cwa'' ([[Humid subtropical climate|monsoon-influenced humid subtropical]]), ''Cwb'' ([[Oceanic climate|subtropical highland]]), ''Dwa'' ([[Humid continental climate#Hot summer subtype|monsoon-influenced hot summer humid continental]]), ''Dwb'' ([[Humid continental climate#Warm summer subtype|monsoon-influenced warm summer humid continental]]), and ''Dsa'' ([[Humid continental climate#Hot summer subtype|Mediterranean-influenced hot summer humid continental]]) on the outskirts and bordering the city; it is mostly ''Dsb'', ''BSk'', and ''Csb''.<ref>{{Cite web|url=https://www.plantmaps.com/koppen-climate-classification-map-united-states.php|title=Interactive United States Koppen-Geiger Climate Classification Map|website=www.plantmaps.com|access-date=April 9, 2020|archive-date=October 11, 2018|archive-url=https://web.archive.org/web/20181011214712/https://www.plantmaps.com/koppen-climate-classification-map-united-states.php|url-status=live}}</ref>

The hottest temperature on record is {{convert|97|F|C}} in July 1973.<ref name=FlagstaffNOAA>{{cite web|url=https://www.weather.gov/wrh/Climate?wfo=fgz|title=NOWData Flagstaff, AZ, forecast office|publisher=[[NOAA]]|access-date=August 5, 2022|archive-date=February 6, 2023|archive-url=https://web.archive.org/web/20230206083626/https://www.weather.gov/wrh/climate?wfo=fgz|url-status=live}}</ref> This is far below a normal summer day in lowland areas of the state. The coldest temperature on record is {{convert|-30|F|C}} in January 1937.<ref name=FlagstaffNOAA/> Warm summer nights are very uncommon with the all-time record being {{convert|68|F|C}} in July 2002 and a regular summer averages a very mild {{convert|59|F|C}} for the warmest low.<ref name=FlagstaffNOAA/> Cold daily maximums are occasional, but rarely severe. The record low high is {{convert|5|F|C}} from January 1963, but the mean for the coldest maximum is relatively close to freezing at {{convert|24|F|C}}.<ref name=FlagstaffNOAA/>

Like most of the state, Northern Arizona experiences a summer monsoon season from July to September,<ref>{{Cite web|url=https://www.weather.gov/fgz/Monsoon|title=Northern Arizona Monsoon Season|last=US Department of Commerce|first=NOAA|website=www.weather.gov|language=EN-US|access-date=April 9, 2020|archive-date=June 24, 2020|archive-url=https://web.archive.org/web/20200624215112/https://www.weather.gov/fgz/Monsoon|url-status=live}}</ref> with Flagstaff's wettest months being July and August, and its driest being June, all in the summer;<ref name=":27" /> Mediterranean climates have [[wet season]] only in the winter.<ref>{{Cite book|last=Dallman|first=Peter R.|title=Plant life in the world's Mediterranean climates: California, Chile, South Africa, Australia, and the Mediterranean Basin|date=1998|publisher=California Native Plant Society|isbn=0520208080|location=Sacramento, CA|oclc=38206653}}</ref> Mediterranean climate categorization does not consider snowfall.<ref>{{Cite thesis |last=Harding |first=Andrew E. |date=2006 |title=Changes in Mediterranean Climate Extremes: Patterns, Causes, and Impacts of Change |chapter-url=https://crudata.uea.ac.uk/cru/pubs/thesis/2006-harding/MCE.2.pdf |chapter=The Mediterranean environment |type=PhD thesis |publisher=[[University of East Anglia]] |page=44 |access-date=April 9, 2020|archive-date=November 28, 2020 |archive-url=https://web.archive.org/web/20201128015618/https://crudata.uea.ac.uk/cru/pubs/thesis/2006-harding/MCE.2.pdf |url-status=live}}</ref>  Semi-arid climates will receive {{convert|10-20|in|mm}} of annual rainfall,<ref>{{Cite web|url=https://www.worldatlas.com/articles/what-are-the-characteristics-of-a-semi-arid-climate-pattern.html|title=What Are The Characteristics Of A Semi-arid Climate Pattern?|website=WorldAtlas|date=November 13, 2017|language=en|access-date=April 9, 2020|archive-date=May 18, 2020|archive-url=https://web.archive.org/web/20200518184748/https://www.worldatlas.com/articles/what-are-the-characteristics-of-a-semi-arid-climate-pattern.html|url-status=live}}</ref> while Flagstaff experiences more.{{efn|See climate data table.|name=climate table}}

Flagstaff's [[hardiness zone]] is mostly 6a, with some areas 5b, meaning plants withstand temperatures down to {{convert|-15|F|C}}.<ref>{{Cite web|url=https://www.plantmaps.com/hardiness-zones-for-flagstaff-arizona|title=Flagstaff, Arizona Hardiness Zones|website=www.plantmaps.com|access-date=April 9, 2020|archive-date=December 2, 2020|archive-url=https://web.archive.org/web/20201202062325/https://www.plantmaps.com/hardiness-zones-for-flagstaff-arizona|url-status=live}}</ref> It is in the Transition [[life zone]];<ref>{{cite web|url=https://www.geo.arizona.edu/Antevs/biomes/azlifzon.html|title=Arizona Life Zones|publisher=Arizona State University|access-date=April 10, 2020|archive-date=November 12, 2020|archive-url=https://web.archive.org/web/20201112014717/https://www.geo.arizona.edu/Antevs/biomes/azlifzon.html|url-status=live}}</ref> the concept of life zones was first observed in the Flagstaff area.<ref>{{Cite book|last=McColl|first=R. W.|title=Encyclopedia of world geography|publisher=Facts On File|year=2005|isbn=978-0816072293|volume=1, A-G|location=New York|oclc=85844781}}</ref> Wind in Flagstaff typically blows southwesterly throughout the year, based on topographical features.<ref name=":29" /> The city's climate data is observed from Flagstaff Pulliam Airport.<ref name=":31">{{Cite journal|last=Hereford|first=Richard|date=2007|title=Climate Variation at Flagstaff, Arizona – 1950 to 2007|url=https://www.researchgate.net/publication/282031501|journal=United States Geological Survey|volume=Open File Report 2007-1410|access-date=April 10, 2020|archive-date=July 19, 2021|archive-url=https://web.archive.org/web/20210719014436/https://www.researchgate.net/publication/282031501_Climate_Variation_at_Flagstaff_Arizona--1950_to_2007|url-status=live}}</ref>

The city receives precipitation every year, with two distinct wet periods in the summer and winter; the summer monsoon season accounts for 34% of annual rainfall, with the winter producing 28%. The summer monsoon season, originating from the Mexican monsoon period, is also wetter than winter, with an average {{convert|7|in|mm}} compared to the winter's {{convert|6|in|mm}}. Before the summer monsoon each year there is a dry period in May and June. Long-term average precipitation is {{convert|21.6|in|mm}} annually, with much heavier rainfall attributed to [[El Niño]] events. Comparatively, [[La Niña]] events have caused below-average rainfall.<ref name=":31" />

Since 1996 the city has been experiencing its driest period, known as the Early-21st Century Drought. As of 2007,{{Update inline|date=February 2023|?=yes|reason=Is there more recent coverage of Flagstaff's drought status?}} Richard Hereford of USGS speculated that the effects of the drought, predicted to last until the late 2020s, may be severe because of Flagstaff's growing population and [[global warming]]. The summer wet season is more reliable and consistent than other times of year, but due to the high temperatures of the area this rainfall is quickly lost to evaporation. During the Early-21st Century Drought, rainfall has been consistently below average in all but the summer season, with temperature averages for all but the summer (which has remained consistent) also increasing.<ref name=":31" />

Equally, snowfall has been lower during the extended dry period,<ref name=":31" /> though the city set a new record for its highest daily snowfall on February 21, 2019, with {{convert|35.9|in|cm}}<ref>{{Cite web|url=https://weather.com/news/news/2019-02-22-flagstaff-arizona-one-day-snowfall-record|title=Flagstaff, Arizona, Shatters Century-Plus Old All-Time Snowiest Day Record|website=The Weather Channel|language=en-US|access-date=April 10, 2020|archive-date=February 4, 2020|archive-url=https://web.archive.org/web/20200204130845/https://weather.com/news/news/2019-02-22-flagstaff-arizona-one-day-snowfall-record|url-status=live}}</ref><ref>{{Cite news|last=Cappucci|first=Matthew|url=https://www.washingtonpost.com/weather/2019/02/22/highly-unusual-event-leaves-arizona-digging-out-inch-snowfall-that-shattered-records/|title='Highly unusual event' leaves Arizona digging out from a {{convert|36|inch|adj=on}} snowfall that shattered records|date=February 22, 2019|newspaper=[[The Washington Post]]|access-date=April 9, 2020|language=en-US|issn=0190-8286|archive-date=February 25, 2019|archive-url=https://web.archive.org/web/20190225083231/https://www.washingtonpost.com/weather/2019/02/22/highly-unusual-event-leaves-arizona-digging-out-inch-snowfall-that-shattered-records/|url-status=live}}</ref> and was still ranked as the United States' third-snowiest city in 2020 (based on 2018–19 [[National Oceanic and Atmospheric Administration]] data). Flagstaff has consistently been among the snowiest cities in the United States,<ref name="FLG_snowfall">
{{cite web|url=http://www.ncdc.noaa.gov/oa/climate/online/ccd/snowfall.html|title=Snowfall&nbsp;– Average Total in Inches|publisher=National Oceanic and Atmospheric Administration|url-status=dead|archive-url=https://web.archive.org/web/20030216070327/http://www.ncdc.noaa.gov/oa/climate/online/ccd/snowfall.html|archive-date=February 16, 2003|access-date=January 28, 2011}}</ref> and snow and winter culture is argued by Michael Weeks to be a large part of Flagstaff's identity.<ref name=":30" /> The Arizona Snowbowl is a major attraction, though it has had to make artificial snow during warmer seasons, and the city tried to launch a bid to be the host city of the [[1960 Winter Olympics]].<ref name=":30" /> The maximum daily snow cover was {{convert|83|in|cm}} on December 20, 1967, although the mean maximum for a full winter is only {{convert|20|in|cm}}. However, due to the infrequent and scattered nature of the snowstorms, persistent [[snowpack]] into spring is rare.<ref name="community_profile2" /> One notable exception occurred during the severe winter of 1915–16, when successive Pacific storms buried the city under over {{convert|70|in|cm|0}} of snow, and some residents were snowbound in their homes for several days.<ref name="NWS">"[http://www.wrh.noaa.gov/psr/general/history/index.php?page=top Arizona’s Most Notable Storms] {{Webarchive|url=https://web.archive.org/web/20110519195508/http://www.wrh.noaa.gov/psr/general/history/index.php?page=top |date=May 19, 2011 }}." ''[[National Weather Service]].'' Retrieved on July 18, 2007.</ref> The earliest seasonal trace of snowfall occurred on September 19, 1965, and the latest on May 29 in both 1971 and 1990.<ref>{{Cite web |title=Earliest and Latest Snowfalls in Flagstaff History |url=https://www.extremeweatherwatch.com/cities/flagstaff/early-late-snow |access-date=May 22, 2023 |website=www.extremeweatherwatch.com |archive-date=May 22, 2023 |archive-url=https://web.archive.org/web/20230522180242/https://www.extremeweatherwatch.com/cities/flagstaff/early-late-snow |url-status=live }}</ref>

Though one of the least-sunny cities in Arizona,<ref>{{Cite web|url=https://www.currentresults.com/Weather/Arizona/annual-days-of-sunshine.php|title=Annual Days of Sunshine in Arizona – Current Results|publisher=www.currentresults.com|access-date=April 10, 2020|archive-date=December 19, 2019|archive-url=https://web.archive.org/web/20191219080608/https://www.currentresults.com/Weather/Arizona/annual-days-of-sunshine.php|url-status=live}}</ref> Flagstaff still ranks among the United States' sunniest cities, having sunshine for an average 78% of the year.<ref name=":29" /> The city receives much more sunshine than other snowy cities, which are primarily in the north of the country.<ref name="TWC">{{cite web|url=http://www.weather.com/weather/wxclimatology/monthly/graph/USAZ0068|title=Seasonal Temperature and Precipitation Information|publisher=The Weather Channel|access-date=February 17, 2009|archive-date=February 8, 2009|archive-url=https://web.archive.org/web/20090208045714/http://www.weather.com/weather/wxclimatology/monthly/graph/USAZ0068|url-status=live}}</ref>

====Seasonal weather====
There are four seasons in Flagstaff, with cool to cold winter temperatures averaging {{convert|45|F|C}} and warm summer temperatures averaging {{convert|80|F|C}}, much cooler than much of Arizona; the average annual snowfall is {{convert|97|in|cm}}.<ref name=":31" /> Spring begins in April with cool or comfortable weather. Sometimes, snow reappears in May, but the spring period is typically mild and dry, lasting until early June. The summer is warm, measured between days when freezing temperatures occur, beginning in June – the last freezing temperature generally in early June – and ending in September. Flagstaff's summer will receive a few days of daytime temperatures above {{convert|90|F|C}}, with much cooler nighttime temperatures typically in the region of {{convert|40|F|C}}. Flagstaff's summers are also notable for the monsoon season in July and August, when thunderstorms occur almost daily. Thunderstorm activity happens mostly during the daytime.<ref name=":29" />

Freezing temperatures (below {{convert|32|F|C}}) return towards the end of September, with the mild fall season having daytime temperatures around {{convert|60|F|C}}.<ref name=":29" /> With its many trees, leaves do change color in Flagstaff's fall, with the change starting at the end of September and happening throughout October.<ref>{{Cite web|url=https://www.flagstaff.com/fall-leaf-colors|title=Best Fall Leaf Colors in Flagstaff {{!}} Fall Leaves in Northern AZ|website=www.flagstaff.com|access-date=April 10, 2020|archive-date=October 30, 2020|archive-url=https://web.archive.org/web/20201030133547/https://www.flagstaff.com/fall-leaf-colors|url-status=live}}</ref> Fall lasts only until the snow comes in November, with winter marked between periods of snowfall, typically from November until mid-April at the latest. Temperatures in winter are usually below freezing, going no higher than around {{convert|40|F|C}} in the day, even in sunshine. Nights can regularly plummet below {{convert|20|F|C}}. A combination of snow cover and [[high pressure]] occurring during winter months will cause the temperature to drop further, once reaching a record low of {{convert|-30|F|C}}. Flagstaff's winter wet season is caused by Pacific storms and lasts from November through April.<ref name=":29" />

{{Flagstaff, Arizona weatherbox}}
{{Graph:Weather monthly history
| table=Ncei.noaa.gov/weather/Flagstaff, Arizona.tab
| title=Flagstaff monthly weather statistics
}}