Editing Boulder, Colorado (section)

==Geography==
[[File:Flatirons Winter Sunrise edit 2.jpg|thumb|upright=1.25|Boulder's rock formations, the [[Flatirons]]]]

The city of Boulder is located in the Boulder Valley, where the [[Rocky Mountains]] meet the [[Great Plains]]. The [[Flatirons]], slabs of sedimentary stone tilted up on the foothills, are located west of the city and are a widely recognized symbol of Boulder.<ref name="Reilly-McNellan">{{cite web|url=http://www-static.bouldercolorado.gov/docs/history-of-mt-parks-mary-reilly-mcnellan-1-201305101210.pdf|author=Mary Reilly-McNellan|title=History of Boulder Mountain Parks|access-date=October 2, 2013|archive-date=September 23, 2020|archive-url=https://web.archive.org/web/20200923195415/https://www-static.bouldercolorado.gov/docs/history-of-mt-parks-mary-reilly-mcnellan-1-201305101210.pdf|url-status=dead}}</ref>

[[Boulder Creek (Colorado)|Boulder Creek]] is the primary flow of water through Boulder. The creek was named before the city's founding and its etymology is unknown. It is from Boulder Creek that the city is believed to have taken its name.{{Citation needed|date=July 2020}} Boulder Creek has significant water flow, derived primarily from snow melt and minor springs west of the city.{{Citation needed|date=July 2020}} The creek flows into [[St. Vrain Creek]] east of [[Longmont]], which is a tributary of the [[South Platte River]].

At the [[2020 United States census]], the city had a total area of {{convert|70.877|km2|acre|order=flip}}, including {{convert|2.689|km2|acre|order=flip}} of water.<ref name=2020_Census/>

The [[40th parallel north|40th parallel]], 40 degrees north latitude, runs through Boulder and can be easily recognized as [[Baseline Road (Colorado)|Baseline Road]] today.

Boulder lies in a wide basin beneath [[Flagstaff Mountain, Boulder, Colorado|Flagstaff Mountain]] just a few miles east of the continental divide and about {{convert|25|mi|km}} northwest of Denver. Arapahoe Glacier provides water for the city, along with Boulder Creek, which flows through the center of the city.<ref>{{cite web |url=http://bcn.boulder.co.us/basin/ |title=Boulder Area Sustainability Information Network |publisher=Boulder Community Network |date=August 27, 1999 |access-date=December 9, 2010 |archive-date=September 28, 2011 |archive-url=https://web.archive.org/web/20110928141035/http://bcn.boulder.co.us/basin/ |url-status=live }}</ref>

[[Denver International Airport]] is located {{convert|33|mi}} east-southeast of Boulder.<ref>"[https://web.archive.org/web/20041208180524/http://www.sirna.com/about/contact.html Contact]." [[Sirna Therapeutics]]. December 8, 2004. Retrieved March 3, 2012. "2950 Wilderness Place Boulder, CO 80301"</ref>

===Environment===
In 1899, government preservation of open space around Boulder began, with the [[Congress of the United States]] approving the allocation of {{convert|1800|acre|km2}} of mountain backdrop/watershed extending from South Boulder Creek to Sunshine Canyon.

====Wildlife protection====
Boulder has created an Urban Wildlife Management Plan which sets policies for managing and protecting urban wildlife.<ref>{{cite web |url=https://bouldercolorado.gov/wildlife/ |title=Urban Wildlife |publisher=Bouldercolorado.gov |access-date=July 23, 2013 |archive-date=October 26, 2013 |archive-url=https://web.archive.org/web/20131026005308/https://bouldercolorado.gov/wildlife |url-status=live }}</ref> The city's Parks and Recreation and Open Space and Mountain Parks departments have volunteers who monitor parks, including wetlands, lakes, etc., to protect ecosystems.<ref>{{cite web |url=https://bouldercolorado.gov/parks-rec/parks-volunteer-opportunities |title=Park Volunteer Opportunities |publisher=Bouldercolorado.gov |date=September 25, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20131026003354/https://bouldercolorado.gov/parks-rec/parks-volunteer-opportunities |archive-date=October 26, 2013 }}</ref> From time to time, parks and hiking trails are closed to conserve or restore ecosystems.<ref>{{cite web |url=https://bouldercolorado.gov/osmp/closures |title=OSMP closures |publisher=Bouldercolorado.gov |access-date=July 23, 2013 |archive-date=August 24, 2013 |archive-url=https://web.archive.org/web/20130824033822/https://bouldercolorado.gov/osmp/closures |url-status=live }}</ref>
Traditionally, Boulder has avoided using chemical [[pesticides]] to control the insect population. However, with the threat of [[West Nile virus]], the city began an integrative plan<ref>[https://web.archive.org/web/20060306113749/http://www.ci.boulder.co.us/environmentalaffairs/ipm/documents/FinalWNVMosquitoPlan.pdf]</ref> to control the mosquito population in 2003 that includes chemical pesticides. Residents can opt out of the program by contacting the city and asking that their areas not be sprayed.<ref>{{cite web |url=https://bouldercolorado.gov/ipm/mosquito-control-program |title=Mosquito Control Program |publisher=Bouldercolorado.gov |date=July 6, 2012 |access-date=July 23, 2013 |archive-date=October 25, 2013 |archive-url=https://web.archive.org/web/20131025223206/https://bouldercolorado.gov/ipm/mosquito-control-program |url-status=live }}</ref>

Under Boulder law, exterminating [[prairie dogs]] requires a permit.<ref>{{cite web |url=http://user.govoutreach.com/boulder/faq.php?cid=23415 |title=Prairie Dogs & Wild Birds Wildlife Protection Ordinance |publisher=City of Boulder |date=January 18, 2005 |access-date=December 9, 2010 |archive-date=June 30, 2014 |archive-url=https://web.archive.org/web/20140630092111/http://user.govoutreach.com/boulder/faq.php?cid=23415 |url-status=live }}</ref>

In 2005, the city experimented with using goats for weed control in environmentally sensitive areas. Goats naturally consume diffuse [[knapweed]] and [[Canada thistle]], and although the program was not as effective as it was hoped, goats will still be considered in future weed control projects. In 2010, goats were used to keep weeds under control at the Boulder Reservoir.<ref>{{cite news
 |title=Goats keep weeds under control at Boulder Reservoir
 |newspaper=Daily Camera
 |date=July 28, 2010
|url=http://www.dailycamera.com/boulder-county-news/ci_15625225
 |access-date=September 3, 2012
|archive-url=https://web.archive.org/web/20130725194601/http://www.dailycamera.com/boulder-county-news/ci_15625225
 |archive-date=July 25, 2013
|url-status=live
 
}}</ref>

The city's Open Space and Mountain Parks department manages approximately {{Convert|8,000|acre|km2}} of protected forest land west of the city, in accordance with a 1999 Forest Ecosystem Management Plan. The plan aims to maintain or enhance native plant and animal species, their communities, the ecological processes that sustain them and to reduce the wildfire risk to forest and human communities.<ref>{{cite web |url=https://bouldercolorado.gov/osmp/forest-ecosystem-management-plan |title=Forest Ecosystem Management Plan |publisher=Bouldercolorado.gov |access-date=May 28, 2018 |archive-date=May 29, 2018 |archive-url=https://web.archive.org/web/20180529130022/https://bouldercolorado.gov/osmp/forest-ecosystem-management-plan |url-status=live }}</ref>

===Climate===
{{climate chart
| Boulder, Colorado
| 21.5 | 47.0 | 0.83
| 22.3 | 48.3 | 0.99
| 29.0 | 57.0 | 1.99
| 34.5 | 62.8 | 3.05
| 42.7 | 71.3 | 3.21
| 51.1 | 82.5 | 1.95
| 57.0 | 88.0 | 1.83
| 55.5 | 86.0 | 1.68
| 48.1 | 78.8 | 2.09
| 37.2 | 65.9 | 1.62
| 28.1 | 54.5 | 1.18
| 21.1 | 46.3 | 0.81
| units  = imperial
| float  = right
| clear  = none
| source = NOAA}}

[[File:The Flatirons in autumn..JPG|thumb|left|Autumn in Boulder]]
[[File:Boulder after a snowfall..JPG|thumb|left|Snowfall is common in Boulder throughout the winter.]]
Boulder has a temperate climate typical for much of the state and receives many sunny or mostly sunny days each year. Boulder is considered [[semi-arid]] (Köppen: ''BSk'') or [[humid subtropical]] (Köppen: ''Cfa'') within the [[Köppen climate classification]] due to its relatively high yearly precipitation and average temperatures remaining above {{convert|32|F|C}} year-round.<ref name="weather.gov">{{cite web |url=https://w2.weather.gov/climate/xmacis.php?wfo=bou |title=Denver/Boulder Weather Forecast Office |access-date=August 10, 2015 |archive-date=May 8, 2021 |archive-url=https://web.archive.org/web/20210508060530/https://w2.weather.gov/climate/xmacis.php?wfo=bou |url-status=live }}</ref><ref>{{cite web|title=Zipcode 80303 – Boulder Colorado is in Hardiness Zones 5b and 6a|website=PlantMaps|access-date=March 21, 2020|url=https://www.plantmaps.com/80303|archive-date=December 16, 2019|archive-url=https://web.archive.org/web/20191216034535/https://www.plantmaps.com/80303|url-status=live}}</ref><ref>{{cite web|title=Boulder, Colorado|url=http://www.weatherbase.com/weather/weather-summary.php3?s=51137&cityname=Boulder%2C+Colorado%2C+United+States+of+America&units=|access-date=March 21, 2020|website=weatherbase|archive-date=March 31, 2022|archive-url=https://web.archive.org/web/20220331133347/http://www.weatherbase.com/weather/weather-summary.php3?s=51137&cityname=Boulder%2C+Colorado%2C+United+States+of+America&units=|url-status=live}}</ref><ref name="Western Regional Climate Center">{{cite web |url=https://wrcc.dri.edu/cgi-bin/cliNORMNCDC2010.pl?co0848 |title=Boulder, Colorado NCDC 1981–2010 Monthly Normals |website=WRCC |access-date=November 17, 2017 |archive-date=September 10, 2015 |archive-url=https://web.archive.org/web/20150910095246/http://www.wrcc.dri.edu/cgi-bin/cliNORMNCDC2010.pl?co0848 |url-status=live }}</ref>

Winter conditions range from generally mild to the occasional bitterly cold. Highs average in the mid to upper 40s °F (7–9&nbsp;°C). There are 4.6 nights annually where the temperature drops to {{convert|0|°F|0}}. Because of [[orographic lift]], the mountains to the west often dry out the air passing over the [[Front Range]], shielding the city from precipitation in winter, though heavy snowfalls may occur. Snowfall averages {{convert|88|in|cm}} per season. Snow depth is usually shallow. Due to the high elevation, a strong warming sun can quickly melt snow cover during the day and [[Chinook wind]]s bring rapid warm-ups throughout the winter months.<ref name=NOAA/>

Summers are warm, with frequent afternoon thunderstorms. There are roughly 30 days of {{convert|90|°F|0}} or above each year.<ref name=NOAA/> [[Diurnal temperature variation]] is typically large due to the high elevation and semi-arid climate. Daytime highs are generally cooler than those of most Colorado cities with similar elevations.

The highest recorded temperature of {{convert|104|°F}} was on June 25, 2012.<ref>{{cite web|title=Weather History: Boulder Airport|url=http://www.wunderground.com/history/airport/KBDU/2012/6/9/MonthlyCalendar.html?req_city=Boulder&req_state=CO&req_statename=&reqdb.zip=80301&reqdb.magic=1&reqdb.wmo=99999|access-date=June 9, 2015|archive-date=July 12, 2015|archive-url=https://web.archive.org/web/20150712083953/http://www.wunderground.com/history/airport/KBDU/2012/6/9/MonthlyCalendar.html?req_city=Boulder&req_state=CO&req_statename=&reqdb.zip=80301&reqdb.magic=1&reqdb.wmo=99999|url-status=live}}</ref> The record low was {{convert|-33|°F|0}} on January 17, 1930. The coldest high temperature, {{convert|-12|°F}}, was on February 4, 1989. The warmest overnight low was on July 20, 1998, with a temperature of {{convert|82|°F}}<ref>{{cite web| url=https://www.esrl.noaa.gov/psd/boulder/dailyrecords| title=Boulder Daily Climatology and Daily Records| access-date=July 10, 2019| archive-date=July 11, 2019| archive-url=https://web.archive.org/web/20190711015911/https://www.esrl.noaa.gov/psd/boulder/dailyrecords/| url-status=live}}</ref>

{{Weather box
|location = Boulder, Colorado, 1991–2020 normals, extremes 1893–present
| single line = Y
|collapsed = Yes
|Jan record high F = 73
|Feb record high F = 79
|Mar record high F = 90
|Apr record high F = 88
|May record high F = 95
|Jun record high F = 104
|Jul record high F = 104
|Aug record high F = 102
|Sep record high F = 100
|Oct record high F = 90
|Nov record high F = 80
|Dec record high F = 76

|Jan avg record high F = 65.4
|Feb avg record high F = 66.4
|Mar avg record high F = 73.9
|Apr avg record high F = 79.5
|May avg record high F = 86.6
|Jun avg record high F = 94.2
|Jul avg record high F = 97.9
|Aug avg record high F = 95.3
|Sep avg record high F = 91.5
|Oct avg record high F = 83.1
|Nov avg record high F = 72.8
|Dec avg record high F = 65.4
|year avg record high F = 98.5

|Jan high F = 47.0
|Feb high F = 48.3
|Mar high F = 57.0
|Apr high F = 62.8
|May high F = 71.3
|Jun high F = 82.5
|Jul high F = 88.0
|Aug high F = 86.0
|Sep high F = 78.8
|Oct high F = 65.9
|Nov high F = 54.5
|Dec high F = 46.3
|year high F = 65.7

|Jan mean F = 34.3
|Feb mean F = 35.3
|Mar mean F = 43.0
|Apr mean F = 48.7
|May mean F = 57.0
|Jun mean F = 66.8
|Jul mean F = 72.5
|Aug mean F = 70.7
|Sep mean F = 63.5
|Oct mean F = 51.6
|Nov mean F = 41.3
|Dec mean F = 33.7
|year mean F =

|Jan low F = 21.5
|Feb low F = 22.3
|Mar low F = 29.0
|Apr low F = 34.5
|May low F = 42.7
|Jun low F = 51.1
|Jul low F = 57.0
|Aug low F = 55.5
|Sep low F = 48.1
|Oct low F = 37.2
|Nov low F = 28.1
|Dec low F = 21.1
|year low F = 37.3

|Jan avg record low F = -0.5
|Feb avg record low F = 0.9
|Mar avg record low F = 10.7
|Apr avg record low F = 19.4
|May avg record low F = 30.1
|Jun avg record low F = 41.3
|Jul avg record low F = 50.0
|Aug avg record low F = 47.4
|Sep avg record low F = 34.7
|Oct avg record low F = 20.1
|Nov avg record low F = 7.9
|Dec avg record low F = 0.4
|year avg record low F = -7.5

|Jan record low F = −33
|Feb record low F = −28
|Mar record low F = −13
|Apr record low F = −3
|May record low F = 17
|Jun record low F = 20
|Jul record low F = 40
|Aug record low F = 40
|Sep record low F = 15
|Oct record low F = −2
|Nov record low F = −12
|Dec record low F = −24

|precipitation colour = green
|Jan precipitation inch = 0.83
|Feb precipitation inch = 0.99
|Mar precipitation inch = 1.99
|Apr precipitation inch = 3.05
|May precipitation inch = 3.21
|Jun precipitation inch = 1.95
|Jul precipitation inch = 1.83
|Aug precipitation inch = 1.68
|Sep precipitation inch = 2.09
|Oct precipitation inch = 1.62
|Nov precipitation inch = 1.18
|Dec precipitation inch = 0.81
|year precipitation inch=

|Jan snow inch = 11.3
|Feb snow inch = 15.0
|Mar snow inch = 15.7
|Apr snow inch = 14.7
|May snow inch = 2.0
|Jun snow inch = 0.0
|Jul snow inch = 0.0
|Aug snow inch = 0.0
|Sep snow inch = 1.0
|Oct snow inch = 7.0
|Nov snow inch = 13.1
|Dec snow inch = 13.0
|year snow inch =

|unit precipitation days = 0.01 in
|Jan precipitation days = 5.8
|Feb precipitation days = 6.9
|Mar precipitation days = 8.1
|Apr precipitation days = 10.1
|May precipitation days = 12.6
|Jun precipitation days = 10.1
|Jul precipitation days = 10.6
|Aug precipitation days = 10.5
|Sep precipitation days = 7.9
|Oct precipitation days = 7.1
|Nov precipitation days = 5.9
|Dec precipitation days = 5.4
|year precipitation days = 101.0

|unit snow days = 0.1 in
|Jan snow days = 5.6
|Feb snow days = 6.5
|Mar snow days = 6.0
|Apr snow days = 4.9
|May snow days = 0.9
|Jun snow days = 0.0
|Jul snow days = 0.0
|Aug snow days = 0.0
|Sep snow days = 0.5
|Oct snow days = 2.1
|Nov snow days = 4.8
|Dec snow days = 5.5
|year snow days =

|Jan snow depth inch = 5.9
|Feb snow depth inch = 6.6
|Mar snow depth inch = 6.5
|Apr snow depth inch = 4.6
|May snow depth inch = 0.8
|Jun snow depth inch = 0.0
|Jul snow depth inch = 0.0
|Aug snow depth inch = 0.0
|Sep snow depth inch = 0.3
|Oct snow depth inch = 3.9
|Nov snow depth inch = 7.0
|Dec snow depth inch = 6.9
|year snow depth inch = 12.9

<!-- Average daylight hours, including cloudy hours. -->
|Jan light = 9.7
|Feb light = 10.7
|Mar light = 12.0
|Apr light = 13.3
|May light = 14.4
|Jun light = 15.0
|Jul light = 14.7
|Aug light = 13.7
|Sep light = 12.4
|Oct light = 11.1
|Nov light = 10.0
|Dec light = 9.4
|year light=
|Jan uv = 2
|Feb uv = 3
|Mar uv = 5
|Apr uv = 7
|May uv = 9
|Jun uv = 11
|Jul uv = 11
|Aug uv = 10
|Sep uv = 7
|Oct uv = 5
|Nov uv = 3
|Dec uv = 2
<!-- Mandatory fields, source -->
|source = NOAA<ref name="National Weather Service">{{cite web
|url=https://w2.weather.gov/climate/xmacis.php?wfo=bou
|title=NOWData – NOAA Online Weather Data
|publisher=NOAA
|access-date=September 8, 2020
|archive-date=May 8, 2021
|archive-url=https://web.archive.org/web/20210508060530/https://w2.weather.gov/climate/xmacis.php?wfo=bou
|url-status=live
}}</ref><ref name=NOAA>{{cite web
|url=https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&stations=USC00050848&format=pdf&dataTypes=MLY-TMAX-NORMAL,MLY-TMIN-NORMAL,MLY-TAVG-NORMAL,MLY-PRCP-NORMAL,MLY-SNOW-NORMAL
|title=U.S. Climate Normals Quick Access
|access-date=August 8, 2022
|archive-date=August 8, 2022
|archive-url=https://web.archive.org/web/20220808215941/https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&stations=USC00050848&format=pdf&dataTypes=MLY-TMAX-NORMAL,MLY-TMIN-NORMAL,MLY-TAVG-NORMAL,MLY-PRCP-NORMAL,MLY-SNOW-NORMAL
|url-status=live
}}</ref>
<!-- For a second source -->
| source 2 = Weather Atlas (daylight)<ref name="WA">{{cite web |url=https://www.weather-us.com/en/colorado-usa/boulder-climate |title=Monthly weather forecast and climate: Boulder, CO |publisher=Weather Atlas |access-date=June 20, 2020 |archive-date=June 21, 2020 |archive-url=https://web.archive.org/web/20200621162717/https://www.weather-us.com/en/colorado-usa/boulder-climate |url-status=live }}</ref>
}}<!-- Infobox ends -->

{{notelist-ua}}