Editing New Orleans (section)

==Geography==
[[File:Satellite image of New Orleans in April 2024.png|thumb|upright=1.15|right|A true-color image captured by [[ESA]]'s [[Sentinel-2A]] in April 2024, New Orleans positioned at the bottom right of the image. [[Lake Pontchartrain]] prominently occupies the central area of the image, while the [[Mississippi River]] can also be observed coursing through the city.]]

New Orleans is located in the [[Mississippi River Delta]], south of [[Lake Pontchartrain]], on the banks of the [[Mississippi River]], approximately {{convert|105|mi|km}} upriver from the [[Gulf of Mexico]]. According to the [[U.S. Census Bureau]], the city's area is {{convert|350|sqmi}}, of which {{convert|169|sqmi}} is land and {{convert|181|sqmi}} (52%) is water.<ref>{{cite web |url=https://www.census.gov//geo/maps-data/data/docs/gazetteer/counties_list_22.txt |publisher=United States Census Bureau |access-date=August 20, 2014 |date=August 22, 2012 |title=2010 Census Gazetteer Files |url-status=dead |archive-url=https://web.archive.org/web/20141006075458/http://www.census.gov/geo/maps-data/data/docs/gazetteer/counties_list_22.txt |archive-date=October 6, 2014}}</ref> The area along the river is characterized by ridges and hollows.

===Elevation===
{{See also|Drainage in New Orleans}}

[[File:New Orleans Levee System.svg|thumb|upright=1.15|right|Vertical cross-section, showing maximum levee height of {{convert|23|ft|m}}]]

New Orleans was originally settled on the river's natural [[levee]]s or high ground. After the [[Flood Control Act of 1965]], the [[United States Army Corps of Engineers|U.S. Army Corps of Engineers]] built floodwalls and man-made levees around a much larger geographic footprint that included previous marshland and swamp. Over time, pumping of water from marshland allowed for development into lower elevation areas. Today, half of the city is at or below local mean sea level, while the other half is slightly above sea level. Evidence suggests that portions of the city may be dropping in elevation due to [[subsidence]].<ref>{{cite web |title=New Study Maps Rate of New Orleans Sinking |url=https://www.nasa.gov/feature/jpl/new-study-maps-rate-of-new-orleans-sinking/ |website=NASA |date=May 16, 2016 |access-date=16 May 2016 |archive-date=March 8, 2021 |archive-url=https://web.archive.org/web/20210308185136/https://www.nasa.gov/feature/jpl/new-study-maps-rate-of-new-orleans-sinking/ |url-status=dead}}</ref>

A 2007 study by [[Tulane University|Tulane]] and [[Xavier University of Louisiana|Xavier University]] suggested that "51%... of the contiguous urbanized portions of Orleans, Jefferson, and St. Bernard parishes lie at or above sea level," with the more densely populated areas generally on higher ground. The average elevation of the city is currently between {{convert|1|and|2|ft|m}} below sea level, with some portions of the city as high as {{convert|20|ft|m|0}} at the base of the river levee in [[Uptown, New Orleans|Uptown]] and others as low as {{convert|7|ft|m|0}} below sea level in the farthest reaches of [[Eastern New Orleans]].<ref>Campanella, R. [http://richcampanella.com/assets/pdf/study_Campanella%20analysis%20on%20Above-Sea-Level%20New%20Orleans.pdf Above-Sea-Level New Orleans] {{Webarchive|url=https://web.archive.org/web/20160304071726/http://richcampanella.com/assets/pdf/study_Campanella%20analysis%20on%20Above-Sea-Level%20New%20Orleans.pdf |date=March 4, 2016 }} April 2007.</ref><ref>Williams, L. [http://blog.nola.com/topnews/2007/04/higher_ground.html Higher Ground] {{Webarchive |url=https://web.archive.org/web/20170819232938/http://blog.nola.com/topnews/2007/04/higher_ground.html |date=August 19, 2017 }} A study finds that New Orleans has plenty of real estate above sea level that is being underutilized. ''The Times Picayune'', April 21, 2007.</ref> A study published by the [[American Society of Civil Engineers|ASCE]] ''[[Journal of Hydrologic Engineering]]'' in 2016, however, stated:

{{blockquote|...most of New Orleans proper—about 65%—is at or below mean sea level, as defined by the average elevation of Lake Pontchartrain<ref>{{Cite journal |doi=10.1061/(ASCE)HE.1943-5584.0001338 |title=Using New Orleans Pumping Data to Reconcile Gauge Observations of Isolated Extreme Rainfall due to Hurricane Isaac |journal=Journal of Hydrologic Engineering |volume=21 |issue=9 |page=05016020 |year=2016 |last1=Schlotzhauer |first1=David |last2=Lincoln |first2=W. Scott| issn = 1084-0699}}</ref>}}

The magnitude of subsidence potentially caused by the draining of natural marsh in the New Orleans area and southeast Louisiana is a topic of debate. A study published in [[Geology (journal)|''Geology'']] in 2006 by an associate professor at Tulane University claims:

{{blockquote|While erosion and wetland loss are huge problems along Louisiana's coast, the basement {{convert|30|ft|m}} to {{convert|50|ft|m}} beneath much of the Mississippi Delta has been highly stable for the past 8,000 years with negligible subsidence rates.<ref>{{cite web |url=http://www2.tulane.edu/news/newwave/072406_a_new_look_at_subsidence_issues.cfm |title=A New Look at Subsidence Issues |author=Strecker, M. |date=July 24, 2006}}{{Dead link |date=May 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>}}

The study noted, however, that the results did not necessarily apply to the Mississippi River Delta, nor the New Orleans metropolitan area proper. On the other hand, a report by the [[American Society of Civil Engineers]] claims that "New Orleans is subsiding (sinking)":<ref name="ASCE">[http://www.asce.org/files/pdf/ERPreport.pdf The New Orleans Hurricane Protection System: What Went Wrong and Why.] {{webarchive |url=https://web.archive.org/web/20070702194739/http://www.asce.org/files/pdf/ERPreport.pdf |date=July 2, 2007 }} Report by the American Society of Civil Engineers.</ref>

{{blockquote|Large portions of Orleans, [[St. Bernard Parish, Louisiana|St. Bernard]], and [[Jefferson Parish, Louisiana|Jefferson]] parishes are currently below sea level—and continue to sink. New Orleans is built on thousands of feet of soft sand, silt, and clay. Subsidence, or settling of the ground surface, occurs naturally due to the consolidation and oxidation of organic soils (called "marsh" in New Orleans) and local groundwater pumping. In the past, flooding and deposition of sediments from the Mississippi River counterbalanced the natural subsidence, leaving southeast Louisiana at or [[Above mean sea level|above sea level]]. However, due to major flood control structures being built upstream on the Mississippi River and levees being built around New Orleans, fresh layers of sediment are not replenishing the ground lost by subsidence.<ref name="ASCE"/>}}

In May 2016, NASA published a study which suggested that most areas were, in fact, experiencing subsidence at a "highly variable rate" which was "generally consistent with, but somewhat higher than, previous studies."<ref>{{cite web |url=https://www.nasa.gov/feature/jpl/new-study-maps-rate-of-new-orleans-sinking |title=New Study Maps Rate of New Orleans Sinking |date=May 16, 2016 |access-date=June 15, 2016 |archive-date=June 8, 2016 |archive-url=https://web.archive.org/web/20160608115437/http://www.nasa.gov/feature/jpl/new-study-maps-rate-of-new-orleans-sinking/ |url-status=dead}}</ref>

===Cityscape===
{{See also|Wards of New Orleans|Neighborhoods in New Orleans}}

[[File:orleans.bourbon.arp.750pix.jpg|right|thumb|[[Bourbon Street]], New Orleans, in 2003, looking towards Canal Street]]
[[File:Colorful houses in New Orleans.jpg|thumb|right|New Orleans contains many distinctive neighborhoods.]]

The [[New Orleans Central Business District|Central Business District]] is located immediately north and west of the Mississippi and was historically called the "American Quarter" or "American Sector". It was developed after the heart of French and Spanish settlement. It includes [[Lafayette Square, New Orleans|Lafayette Square]]. Most streets in this area fan out from a central point. Major streets include [[Canal Street, New Orleans|Canal Street]], Poydras Street, Tulane Avenue and Loyola Avenue. Canal Street divides the traditional "[[Downtown New Orleans|downtown]]" area from the "[[Uptown New Orleans|uptown]]" area.

Every street crossing Canal Street between the Mississippi River and [[Rampart Street]], which is the northern edge of the French Quarter, has a different name for the "uptown" and "downtown" portions. For example, [[St. Charles Avenue]], known for its street car line, is called [[Royal Street, New Orleans|Royal Street]] below Canal Street, though where it traverses the Central Business District between Canal and Lee Circle, it is properly called St. Charles Street.<ref>Brock, Eric J. ''New Orleans'', Arcadia Publishing, Charleston, South Carolina (1999), pp. 108–09.</ref> Elsewhere in the city, Canal Street serves as the dividing point between the "South" and "North" portions of various streets. In the local [[wikt:parlance|parlance]] ''downtown'' means "downriver from Canal Street", while ''uptown'' means "upriver from Canal Street". Downtown neighborhoods include the French Quarter, [[Tremé]], the [[7th Ward of New Orleans|7th Ward]], [[Faubourg Marigny]], [[Bywater, New Orleans|Bywater]] (the Upper Ninth Ward), and the Lower [[Ninth Ward of New Orleans|Ninth Ward]]. [[Uptown New Orleans|Uptown]] neighborhoods include the Warehouse District, the [[Lower Garden District, New Orleans|Lower Garden District]], the [[Garden District, New Orleans|Garden District]], the [[Irish Channel, New Orleans|Irish Channel]], the University District, [[Carrollton, Louisiana|Carrollton]], [[Gert Town, New Orleans|Gert Town]], [[Fontainebleau, New Orleans|Fontainebleau]] and [[Broadmoor, New Orleans|Broadmoor]]. However, the Warehouse and the Central Business District are frequently called "Downtown" as a specific region, as in the Downtown Development District.

Other major districts within the city include [[Bayou St. John (neighborhood)|Bayou St. John]], [[Mid-City New Orleans|Mid-City]], [[Gentilly, New Orleans|Gentilly]], [[Lakeview, New Orleans|Lakeview]], Lakefront, [[Eastern New Orleans|New Orleans East]] and [[Algiers, New Orleans|Algiers]].

====Historic and residential architecture====
{{See also|Buildings and architecture of New Orleans}} New Orleans is world-famous for its abundance of architectural styles that reflect the city's multicultural heritage. Though New Orleans possesses numerous structures of national architectural significance, it is equally, if not more, revered for its enormous, largely intact (even post-Katrina) historic built environment. Twenty National Register Historic Districts have been established, and fourteen local historic districts aid in preservation. Thirteen of the districts are administered by the New Orleans Historic District Landmarks Commission (HDLC), while one—the French Quarter—is administered by the Vieux Carre Commission (VCC). Additionally, both the [[National Park Service]], via the [[National Register of Historic Places]], and the HDLC have landmarked individual buildings, many of which lie outside the boundaries of existing historic districts.<ref>{{cite web |url=http://www.nolamasterplan.org/documentsandrresources.asp |title=Part 2-The Plan; Section 1-How We Live; Map-Local and National Register Historic Districts |url-status=dead |archive-url=https://web.archive.org/web/20160115105708/http://www.nolamasterplan.org/documentsandrresources.asp |archive-date=January 15, 2016}}</ref>

Housing styles include the [[shotgun house]] and the [[bungalow]] style. Creole cottages and townhouses, notable for their large courtyards and intricate iron balconies, line the streets of the French Quarter. American townhouses, double-gallery houses, and Raised Center-Hall Cottages are notable. [[St. Charles Avenue]] is famed for its large [[Antebellum architecture|antebellum homes]]. Its mansions are in various styles, such as [[Greek Revival architecture|Greek Revival]], [[American colonial architecture|American Colonial]] and the [[Victorian architecture|Victorian]] styles of [[Queen Anne style architecture in the United States|Queen Anne]] and [[Italianate architecture]]. New Orleans is also noted for its large, European-style Catholic cemeteries.

====Tallest buildings====
{{See also|List of tallest buildings in New Orleans}}
[[File:New Orleans Skyline from Uptown.jpg|thumb|right|upright=2.5|Skyline of the [[New Orleans Central Business District|Central Business District]] of New Orleans]]
For much of its history, New Orleans' skyline displayed only low- and mid-rise structures. The soft soils are susceptible to subsidence, and there was doubt about the feasibility of constructing high rises. Developments in engineering throughout the 20th century eventually made it possible to build sturdy foundations in the foundations that underlie the structures. In the 1960s, the [[2 Canal Street|World Trade Center New Orleans]] and [[Plaza Tower]] demonstrated skyscrapers' viability. [[One Shell Square]] became the city's tallest building in 1972. The oil boom of the 1970s and early 1980s redefined New Orleans' skyline with the development of the Poydras Street corridor. Most are clustered along [[Canal Street, New Orleans|Canal Street]] and Poydras Street in the Central Business District.

{| class="wikitable"
|-
! Name
! Stories
! Height
|-
| [[One Shell Square]] || 51 || {{cvt|697|ft|m}}
|-
| [[Place St. Charles]] || 53 || {{cvt|645|ft|m}}
|-
| [[Plaza Tower]] || 45 || {{cvt|531|ft|m}}
|-
| [[Energy Centre]] || 39 || {{cvt|530|ft|m}}
|-
| [[First Bank and Trust Tower]] || 36 || {{cvt|481|ft|m}}
|}

===Climate===
{{See also|Hurricane preparedness for New Orleans}}
<div style="width:100%;"></div>

[[File:Snow in New Orleans by evreniz.jpg|thumb|upright=1.15|right|Snow falls on [[St. Charles Avenue]] in December 2008.]]The climate of New Orleans is [[Humid subtropical climate|humid subtropical]] ([[Köppen climate classification|Köppen]]: ''Cfa''), with short, generally mild winters and hot, humid summers; in the 1991–2020 climate normals the USDA hardiness zone is 9b, with the coldest temperature in most years being about {{convert|27.6|°F|1}}. The monthly daily average temperature ranges from {{convert|54.3|°F|1}} in January to {{convert|84|°F|1}} in August. Officially, as measured at New Orleans International Airport, temperature records range from {{convert|11|to|105|F|C}} [[December 1989 United States cold wave|on December 23, 1989]], and August 27, 2023, respectively; Audubon Park has recorded temperatures ranging from {{convert|6|°F}} on [[Great Blizzard of 1899|February 13, 1899]], up to {{convert|104|°F}} on June 24, 2009, and August 28, 2023.<ref name="NWS New Orleans/Baton Rouge, LA (LIX)"/> Dewpoints in the summer months (June–August) are relatively high, ranging from {{convert|21.7|to|23.0|C|F|order=flip}}.<ref name="WMO 1961–90 KMSY"/>

The average precipitation is {{convert|62.5|in|sigfig=3}} annually; the summer months are the wettest, while October is the driest month.<ref name="NWS New Orleans/Baton Rouge, LA (LIX)"/> Precipitation in winter usually accompanies the passing of a cold front. There are a median of over 80 days of {{convert|90|°F|0}}+ highs, 9 days per winter where the high does not exceed {{convert|50|°F|0}}, and less than 8 nights with freezing lows annually, although it is not uncommon for entire winter seasons to pass with no freezing temperatures at all, such as the 2003–04 winter, the 2012–13 winter, the 2015–16 winter and the consecutive winters of 2018–19 and 2019–20. It is rare for the temperature to reach {{convert|20|or|100|°F|°C}}, with the last occurrence of each being January 17, 2018, and August 27, 2023, respectively.<ref name="NWS New Orleans/Baton Rouge, LA (LIX)"/><ref>{{Cite web |last=US Department of Commerce |first=NOAA |title=2023 Summer Heat & Climatology |url=https://www.weather.gov/lix/2023summerheat |access-date=2024-07-05 |website=www.weather.gov |language=EN-US}}</ref>

New Orleans experiences snowfall only on rare occasions. A small amount of snow fell during the [[2004 Christmas Eve Snowstorm]] and again on [[Christmas]] (December 25) when a combination of rain, sleet, and snow fell on the city, leaving some bridges icy. The [[New Year's Eve 1963 snowstorm]] affected New Orleans and brought {{convert|4.5|in|cm}}. Snow fell again on December 22, 1989, during the [[December 1989 United States cold wave]], when most of the city received {{convert|1|–|2|in|cm}}.

The last significant snowfall in New Orleans was on [[January 20–22, 2025 Gulf Coast blizzard|January 21, 2025]], when the city received {{convert|8|-|10|in|cm}} of snow.<ref>{{cite web |first1=WWL |title=How much snow did New Orleans get? |url=https://www.wwltv.com/article/weather/weather-impact/how-much-snow-did-new-orleans-get-historic-new-orleans-winters-storm/289-ac64ab08-cbd4-4d5a-862f-8adb875f1be3 |access-date=22 January 2025}}</ref> {{Weather box
| location = [[Louis Armstrong New Orleans International Airport]] (1991–2020 normals,{{efn|Mean monthly maxima and minima (i.e. the expected highest and lowest temperature readings at any point during the year or given month) calculated based on data at said location from 1991 to 2020}} extremes 1946–present){{efn|Official records for New Orleans have been kept at MSY since May 1, 1946.<ref>{{cite web |url=http://threadex.rcc-acis.org/ |title=Threaded Extremes |website=threadex.rcc-acis.org |access-date=September 3, 2016 |archive-date=March 5, 2020 |archive-url=https://web.archive.org/web/20200305195121/http://threadex.rcc-acis.org/ |url-status=live }}</ref> Additional records from Audubon Park dating back to 1893 have also been included.}}
| single line = Y
| collapsed = Y
| Jan record high F = 83
| Feb record high F = 85
| Mar record high F = 89
| Apr record high F = 92
| May record high F = 97
| Jun record high F = 101
| Jul record high F = 101
| Aug record high F = 105
| Sep record high F = 101
| Oct record high F = 97
| Nov record high F = 88
| Dec record high F = 85
| year record high F = 105
| Jan avg record high F = 77.5
| Feb avg record high F = 79.7
| Mar avg record high F = 82.9
| Apr avg record high F = 86.5
| May avg record high F = 91.9
| Jun avg record high F = 95.2
| Jul avg record high F = 96.6
| Aug avg record high F = 96.7
| Sep avg record high F = 94.3
| Oct avg record high F = 89.8
| Nov avg record high F = 83.8
| Dec avg record high F = 80.3
| year avg record high F = 97.6
| Jan high F = 62.5
| Feb high F = 66.4
| Mar high F = 72.3
| Apr high F = 78.5
| May high F = 85.3
| Jun high F = 90.0
| Jul high F = 91.4
| Aug high F = 91.3
| Sep high F = 88.1
| Oct high F = 80.6
| Nov high F = 71.2
| Dec high F = 64.8
| year high F = 78.5
| Jan mean F = 54.3
| Feb mean F = 58.0
| Mar mean F = 63.8
| Apr mean F = 70.1
| May mean F = 77.1
| Jun mean F = 82.4
| Jul mean F = 83.9
| Aug mean F = 84.0
| Sep mean F = 80.8
| Oct mean F = 72.5
| Nov mean F = 62.4
| Dec mean F = 56.6
| year mean F = 70.5
| Jan low F = 46.1
| Feb low F = 49.7
| Mar low F = 55.3
| Apr low F = 61.7
| May low F = 69.0
| Jun low F = 74.7
| Jul low F = 76.5
| Aug low F = 76.6
| Sep low F = 73.5
| Oct low F = 64.3
| Nov low F = 53.7
| Dec low F = 48.4
| year low F = 62.5
| Jan avg record low F = 29.5
| Feb avg record low F = 33.4
| Mar avg record low F = 38.0
| Apr avg record low F = 47.1
| May avg record low F = 57.3
| Jun avg record low F = 67.4
| Jul avg record low F = 71.4
| Aug avg record low F = 71.1
| Sep avg record low F = 63.3
| Oct avg record low F = 47.7
| Nov avg record low F = 37.7
| Dec avg record low F = 32.6
| year avg record low F = 27.6
| Jan record low F = 14
| Feb record low F = 16
| Mar record low F = 25
| Apr record low F = 32
| May record low F = 41
| Jun record low F = 50
| Jul record low F = 60
| Aug record low F = 60
| Sep record low F = 42
| Oct record low F = 35
| Nov record low F = 24
| Dec record low F = 11
| year record low F = 11
| precipitation colour = green
| Jan precipitation inch = 5.18
| Feb precipitation inch = 4.13
| Mar precipitation inch = 4.36
| Apr precipitation inch = 5.22
| May precipitation inch = 5.64
| Jun precipitation inch = 7.62
| Jul precipitation inch = 6.79
| Aug precipitation inch = 6.91
| Sep precipitation inch = 5.11
| Oct precipitation inch = 3.70
| Nov precipitation inch = 3.87
| Dec precipitation inch = 4.82
| year precipitation inch = 63.35
| unit precipitation days = 0.01 in
| Jan precipitation days = 9.5
| Feb precipitation days = 9.0
| Mar precipitation days = 8.1
| Apr precipitation days = 7.3
| May precipitation days = 7.8
| Jun precipitation days = 12.7
| Jul precipitation days = 13.9
| Aug precipitation days = 13.6
| Sep precipitation days = 9.8
| Oct precipitation days = 7.1
| Nov precipitation days = 7.1
| Dec precipitation days = 9.2
| year precipitation days = 115.1
| Jan humidity = 75.6
| Feb humidity = 73.0
| Mar humidity = 72.9
| Apr humidity = 73.4
| May humidity = 74.4
| Jun humidity = 76.4
| Jul humidity = 79.2
| Aug humidity = 79.4
| Sep humidity = 77.8
| Oct humidity = 74.9
| Nov humidity = 77.2
| Dec humidity = 76.9
| year humidity = 75.9
| Jan sun = 153.0
| Feb sun = 161.5
| Mar sun = 219.4
| Apr sun = 251.9
| May sun = 278.9
| Jun sun = 274.3
| Jul sun = 257.1
| Aug sun = 251.9
| Sep sun = 228.7
| Oct sun = 242.6
| Nov sun = 171.8
| Dec sun = 157.8
| Jan percentsun = 47
| Feb percentsun = 52
| Mar percentsun = 59
| Apr percentsun = 65
| May percentsun = 66
| Jun percentsun = 65
| Jul percentsun = 60
| Aug percentsun = 62
| Sep percentsun = 62
| Oct percentsun = 68
| Nov percentsun = 54
| Dec percentsun = 50
| year percentsun = 60
| source 1 = [[NOAA]] (relative humidity and sun 1961–1990){{efn|Sunshine normals are based on only 20 to 22 years of data.}}<ref name = "NWS New Orleans/Baton Rouge, LA (LIX)">{{cite web |url=https://w2.weather.gov/climate/xmacis.php?wfo=lix |title=NOWData – NOAA Online Weather Data |publisher=National Oceanic and Atmospheric Administration |access-date=May 25, 2021 |archive-date=July 13, 2021 |archive-url=https://web.archive.org/web/20210713174234/https://w2.weather.gov/climate/xmacis.php?wfo=lix |url-status=live }}</ref><ref name = "NOAA txt">{{cite web |url=https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USW00012916&format=pdf |title=Station: New Orleans INTL AP, LA |publisher=National Oceanic and Atmospheric Administration |work=U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020) |access-date=May 25, 2021 |archive-date=December 4, 2021 |archive-url=https://web.archive.org/web/20211204114448/https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USW00012916&format=pdf |url-status=live }}</ref><ref name="WMO 1961–90 KMSY" >{{cite web |url=ftp://ftp.atdd.noaa.gov/pub/GCOS/WMO-Normals/TABLES/REG_IV/US/GROUP3/72231.TXT |title=WMO Climate Normals for NEW ORLEANS, LA 1961–1990 |access-date=March 27, 2014 |publisher=National Oceanic and Atmospheric Administration |archive-date=July 16, 2020 |archive-url=https://web.archive.org/web/20200716200232/ftp://ftp.atdd.noaa.gov/pub/GCOS/WMO-Normals/TABLES/REG_IV/US/GROUP3/72231.TXT |url-status=live }}</ref>
| source = 
}}
{{Weather box
| location = [[Audubon Park, New Orleans]] (1991–2020 normals, extremes 1893–present)
| single line = Y
| collapsed = Y
| Jan record high F = 84
| Feb record high F = 86
| Mar record high F = 91
| Apr record high F = 93
| May record high F = 99
| Jun record high F = 104
| Jul record high F = 102
| Aug record high F = 104
| Sep record high F = 101
| Oct record high F = 97
| Nov record high F = 92
| Dec record high F = 85
| year record high F = 104
| Jan high F = 64.3
| Feb high F = 68.4
| Mar high F = 74.5
| Apr high F = 80.9
| May high F = 87.9
| Jun high F = 92.5
| Jul high F = 93.9
| Aug high F = 94.0
| Sep high F = 90.1
| Oct high F = 82.6
| Nov high F = 72.9
| Dec high F = 66.4
| year high F = 80.7
| Jan mean F = 55.4
| Feb mean F = 59.4
| Mar mean F = 65.2
| Apr mean F = 71.4
| May mean F = 78.6
| Jun mean F = 83.7
| Jul mean F = 85.2
| Aug mean F = 85.5
| Sep mean F = 81.8
| Oct mean F = 73.6
| Nov mean F = 63.7
| Dec mean F = 57.7
| year mean F = 71.8
| Jan low F = 46.5
| Feb low F = 50.5
| Mar low F = 55.8
| Apr low F = 62.0
| May low F = 69.3
| Jun low F = 74.9
| Jul low F = 76.6
| Aug low F = 76.9
| Sep low F = 73.6
| Oct low F = 64.7
| Nov low F = 54.6
| Dec low F = 49.0
| year low F = 62.9
| Jan record low F = 13
| Feb record low F = 6
| Mar record low F = 26
| Apr record low F = 32
| May record low F = 46
| Jun record low F = 54
| Jul record low F = 61
| Aug record low F = 60
| Sep record low F = 49
| Oct record low F = 35
| Nov record low F = 26
| Dec record low F = 12
| year record low F = 6
| precipitation colour = green
| Jan precipitation inch = 4.95
| Feb precipitation inch = 4.14
| Mar precipitation inch = 4.60
| Apr precipitation inch = 4.99
| May precipitation inch = 5.39
| Jun precipitation inch = 7.37
| Jul precipitation inch = 8.77
| Aug precipitation inch = 6.80
| Sep precipitation inch = 5.72
| Oct precipitation inch = 3.58
| Nov precipitation inch = 3.78
| Dec precipitation inch = 4.51
| year precipitation inch = 64.60
| unit precipitation days = 0.01 in
| Jan precipitation days = 9.8
| Feb precipitation days = 8.9
| Mar precipitation days = 7.5
| Apr precipitation days = 7.0
| May precipitation days = 7.4
| Jun precipitation days = 12.6
| Jul precipitation days = 15.1
| Aug precipitation days = 13.3
| Sep precipitation days = 10.0
| Oct precipitation days = 6.8
| Nov precipitation days = 7.3
| Dec precipitation days = 8.8
| year precipitation days = 114.5
| source 1 = NOAA<ref name = "NWS New Orleans/Baton Rouge, LA (LIX)"/><ref>{{cite web |url=https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USW00012930&format=pdf |title=Station: New Orleans Audubon, LA |work=U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020) |publisher=National Oceanic and Atmospheric Administration |access-date=August 27, 2021 |archive-date=October 27, 2021 |archive-url=https://web.archive.org/web/20211027190832/https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USW00012930&format=pdf |url-status=live }}</ref>
| source = 
}}

===Threat from tropical cyclones===

[[File:Hurricanes Category 3 or greater within 100 miles of New Orleans.jpg|thumb|upright=1.15|Hurricanes of Category 3 or greater passing within 100 miles, from 1852 to 2005 ([[NOAA]])|alt=]]

[[Tropical cyclone|Hurricanes]] pose a severe threat to the area, and the city is particularly at risk due to its low elevation, the city being surrounded by water from the north, east, and south, and Louisiana's sinking coast.<ref name="Katrina">{{cite book |last=Tidwell |first=Mike |title=The Ravaging Tide: Strange Weather, Future Katrinas, and the Coming Death of America's Coastal Cities |url=https://books.google.com/books?id=9cFajSK4cjIC |year=2006 |publisher=Simon and Schuster |isbn=978-1-4165-3810-3 |access-date=January 10, 2024 |archive-date=January 10, 2024 |archive-url=https://web.archive.org/web/20240110085307/https://books.google.com/books?id=9cFajSK4cjIC |url-status=live }}</ref> According to the [[Federal Emergency Management Agency]], New Orleans is the nation's most vulnerable city to hurricanes.<ref>{{Cite web |url=http://www.fema.gov/emergency/reports/2006/nat112006.shtm |archive-url=https://web.archive.org/web/20120703204951/http://www.fema.gov/emergency/reports/2006/nat112006.shtm |url-status=dead |title=Federal Emergency Management Agency |archive-date=July 3, 2012}}</ref> Indeed, portions of [[New Orleans metropolitan area|Greater New Orleans]] have been flooded by the [[Grand Isle Hurricane of 1909]],<ref name="ReferenceB">See [[Hurricane preparedness for New Orleans#Early 20th century hurricanes]]</ref> the [[New Orleans Hurricane of 1915]],<ref name="ReferenceB"/> [[1947 Fort Lauderdale Hurricane]],<ref name="ReferenceB"/> [[Hurricane Flossy]]<ref>See [[Hurricane preparedness for New Orleans#Late 20th century hurricanes]]</ref> in 1956, [[Hurricane Betsy]] in 1965, [[Hurricane Georges]] in 1998, Hurricanes [[Hurricane Katrina|Katrina]] and [[Hurricane Rita|Rita]] in 2005, [[Hurricane Gustav]] in 2008, [[Hurricane Isaac (2012)|Hurricane Isaac]] in 2012, [[Hurricane Zeta]] in 2020 (Zeta was also the most intense hurricane to pass over New Orleans) and [[Hurricane Ida]] in 2021. The flooding from Betsy was significant and in a few neighborhoods severe, and that from Katrina was disastrous for the majority of the city.<ref>{{cite news |url=https://www.nytimes.com/2008/09/13/us/13ike.html |title=Huge Storm Slams Into Coast of Texas |first1=James C. Jr. |last1=McKinley |first2=Ian |last2=Urbina |newspaper=The New York Times |date=September 12, 2008 |access-date=February 22, 2017 |archive-date=April 12, 2017 |archive-url=https://web.archive.org/web/20170412123248/http://www.nytimes.com/2008/09/13/us/13ike.html |url-status=live }}</ref><ref>[http://www.cnn.com/2005/US/09/24/rita.assess/index.html Rita's impact, city by city. Flooding and power outages plague Texas and Louisiana.] {{Webarchive|url=https://web.archive.org/web/20071115115620/http://www.cnn.com/2005/US/09/24/rita.assess/index.html |date=November 15, 2007 }} CNN, September 24, 2005.</ref><ref>{{cite web |title=The Weather Channel's Special Report: Vulnerable Cities – New Orleans, Louisiana |url=http://www.weather.com/newscenter/specialreports/hurricanes/vulnerablecities/neworleans.html |access-date=October 26, 2006 |archive-url=https://web.archive.org/web/20060427160836/http://www.weather.com/newscenter/specialreports/hurricanes/vulnerablecities/neworleans.html <!-- Bot retrieved archive --> |archive-date=April 27, 2006}}</ref>

On August 29, 2005, storm surge from Hurricane Katrina caused catastrophic failure of the [[Flood Control Act of 1965|federally designed and built]] levees, flooding 80% of the city.<ref>{{usurped|1=[https://web.archive.org/web/20050910190054/http://news.nationalgeographic.com/news/2005/08/photogalleries/New_Orleans_flood/ "New Orleans People, Pets Flee Flood (photographs)"]}} ''National Geographic'', August 30, 2005.</ref><ref>[http://www.cnn.com/2005/WEATHER/08/30/katrina.neworleans/index.html Floodwaters, tensions rise in New Orleans.] {{webarchive |url=https://web.archive.org/web/20081218083246/http://www.cnn.com/2005/WEATHER/08/30/katrina.neworleans/index.html |date=December 18, 2008 }} CNN, August 31, 2005.</ref> A report by the American Society of Civil Engineers says that "had the levees and floodwalls not failed and had the pump stations operated, nearly two-thirds of the deaths would not have occurred".<ref name="ASCE"/>

New Orleans has always had to consider the risk of hurricanes, but the risks are dramatically greater today due to coastal erosion from human interference.<ref name="barry">{{cite web |url=http://johnmbarry.com/bio.htm |title=What You Need to Know About Katrina – and Don't – Why It Makes Economic Sense to Protect and Rebuild New Orleans |author=Barry, J.M. |access-date=December 11, 2007 |archive-date=January 12, 2008 |archive-url=https://web.archive.org/web/20080112075941/http://johnmbarry.com/bio.htm |url-status=live }}</ref> Since the beginning of the 20th century, it has been estimated that Louisiana has lost {{convert|2000|sqmi|km2|-3}} of coast (including many of its barrier islands), which once protected New Orleans against storm surge. Following Hurricane Katrina, the Army Corps of Engineers has instituted massive levee repair and hurricane protection measures to protect the city.

In 2006, Louisiana voters overwhelmingly adopted an amendment to the state's constitution to dedicate all revenues from off-shore drilling to restore Louisiana's eroding coast line.<ref>[http://gov.louisiana.gov/index.cfm?articleID=2439&md=newsroom&tmp=detail President Bush signs OCS revenue sharing bill; Statement by Governor Kathleen Babineaux Blanco.] {{Webarchive|url=https://web.archive.org/web/20071107163356/http://gov.louisiana.gov/index.cfm?articleID=2439&md=newsroom&tmp=detail |date=November 7, 2007 }} From: gov.louisiana.gov, December 20, 2006.</ref> U.S. Congress has allocated $7 billion to bolster New Orleans' flood protection.<ref>Walsh, B. [http://www.nola.com/news/t-p/washington/index.ssf?/base/news-2/1192603358244350.xml&coll=1 Blanco, Nagin lobby for Louisiana aid.] {{webarchive |url=https://web.archive.org/web/20090701222201/http://www.nola.com/news/t-p/washington/index.ssf?%2Fbase%2Fnews-2%2F1192603358244350.xml&coll=1 |date=July 1, 2009 }} ''The Times Picayune'', October 17, 2007.</ref>

According to a study by the [[National Academy of Engineering]] and the [[United States National Research Council|National Research Council]], levees and floodwalls surrounding New Orleans—no matter how large or sturdy—cannot provide absolute protection against overtopping or failure in extreme events. Levees and floodwalls should be viewed as a way to reduce risks from hurricanes and storm surges, not as measures that eliminate risk. For structures in hazardous areas and residents who do not relocate, the committee recommended major [[Flood mitigation#Protection of individual properties|floodproofing]] measures—such as elevating the first floor of buildings to at least the 100-year flood level.<ref>[http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=12647 "Levees Cannot Fully Eliminate Risk of Flooding to New Orleans"] {{Webarchive|url=https://web.archive.org/web/20090428070859/http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=12647 |date=April 28, 2009 }} National Academy of Sciences, April 24, 2009</ref>