Editing Sarnia (section)

===Climate===
Sarnia has a humid continental climate ([[Köppen climate classification]] ''Dfb''), verging on the hot summer subtype ''Dfa''.<ref>{{cite web|title=Koeppen-Geiger Climate Classification|url=http://koeppen-geiger.vu-wien.ac.at/present.htm|publisher=Koeppen-Geiger|access-date=7 July 2013}}</ref> Winters are cold with a few short-lasting [[Arctic front|Arctic air masses]] that dip far enough south and bring with them daily high temperatures below {{Convert|−10|C}}.<ref name="climate"/>  Sarnia, while not quite located in the southwestern Ontario snowbelt, sometimes receives large quantities of [[lake-effect snow]]. Sarnia averages {{convert|112.0|cm|abbr=on}} of snow per year, while London, inland and to the east, averages {{convert|194.3|cm|abbr=on}}.

The moderating effect of Lake Huron which Sarnia has a long shoreline on its north side, and to a lesser extent other nearby [[Great Lakes]] ensure seasonal lag similar to other lakeside locations over much of Southern Ontario. This gives Sarnia a noticeably milder period following Summer and delaying onset of the first frost in the Fall.<ref>{{cite web|date=22 June 2011|title=Sarnia Climate and Location|url=http://www.sarnia.ca/visit.asp?sectionid=432|url-status=dead|archive-url=https://web.archive.org/web/20131002163405/http://www.sarnia.ca/visit.asp?sectionid=432|archive-date=2 October 2013|access-date=17 April 2012|publisher=City of Sarnia}}</ref> Conversely, cooler average daytime temperatures tend to prevail for longer after winter breaks, through the late Spring and early Summer as compared to further inland.  
Daily lows of less than {{Convert|−10|C}} occur an average of 29 days a year, and less than {{Convert|−20|C}}, only average two days a year. 
Summers are warm with typically humid conditions. [[Humidex]] readings and [[Dew Point]]s can be very high at times from late May to late September. Sarnia has the second greatest number of high humidex days at or above {{Convert|35|C}} (with 23.16 days on average per year) and humidex days at or above {{Convert|30|C}} (with 61.20 days on average per year) in Canada, ranking after [[Windsor, Ontario]].<ref>{{cite web|title=Weather Stats: Weather Winners|url=http://www.weatherstats.ca/winners.html?68|access-date=5 September 2013}}</ref> [[Thunderstorm]]s are frequent and can occasionally become severe from April to September.<ref>{{cite web |url=http://climate.weatheroffice.gc.ca/climate_normals/results_e.html?stnID=4589&lang=e&dCode=1&province=ONT&provBut=&month1=0&month2=12 |title=National Climate Data and Information Archive, 1971–2000 |publisher=Government of Canada |access-date=12 April 2012}}</ref> Destructive weather is very rare in the area but has occurred, such as the [[1953 Sarnia tornado|tornado event of 1953]].

{{Weather box
|metric first= Y
|single line= Y
|location= Sarnia ([[Sarnia Chris Hadfield Airport|Chris Hadfield Airport]]), 1991&ndash;2020 normals, extremes 1926&ndash;present{{efn|Extreme high and low-temperature data was recorded at Sarnia from November 1926 to July 1927 and from November 1948 to January 1961, at [[Polymer Corporation|Sarnia Polysar]] from February 1961 to November 1967 and at Sarnia Airport from December 1967 to present.}}
|Jan record high C = 18.9
|Feb record high C = 19.4
|Mar record high C = 28.2
|Apr record high C = 31.2
|May record high C = 34.4
|Jun record high C = 40.1
|Jul record high C = 37.3
|Aug record high C = 37.9
|Sep record high C = 37.2
|Oct record high C = 32.5
|Nov record high C = 26.7
|Dec record high C = 18.0
|year record high C = 40.1
|Jan high C = -0.9
|Feb high C = 0.0
|Mar high C = 5.0
|Apr high C = 11.9
|May high C = 18.7
|Jun high C = 24.0
|Jul high C = 26.5
|Aug high C = 25.5
|Sep high C = 22.2
|Oct high C = 15.4
|Nov high C = 8.0
|Dec high C = 2.1
|year high C = 13.2
|Jan mean C = -4.6
|Feb mean C = -4.0
|Mar mean C = 0.6
|Apr mean C = 6.7
|May mean C = 13.1
|Jun mean C = 18.6
|Jul mean C = 21.3
|Aug mean C = 20.4
|Sep mean C = 16.7
|Oct mean C = 10.7
|Nov mean C = 4.2
|Dec mean C = -1.2
|year mean C = 8.5
|Jan low C = -8.2
|Feb low C = -7.9
|Mar low C = -3.7
|Apr low C = 1.5
|May low C = 7.1
|Jun low C = 13.0
|Jul low C = 16.0
|Aug low C = 15.3
|Sep low C = 11.3
|Oct low C = 6.0
|Nov low C = 0.4
|Dec low C = -4.4
|year low C = 3.9 
|Jan record low C = -28.9
|Feb record low C = -28.3
|Mar record low C = -25.6
|Apr record low C = -11.7
|May record low C = -5.0
|Jun record low C = -1.1
|Jul record low C = 4.4
|Aug record low C = 1.2
|Sep record low C = -1.6
|Oct record low C = -8.9
|Nov record low C = -15.0
|Dec record low C = -25.0
|year record low C = -28.9
|precipitation colour = green
|Jan precipitation mm = 56.5
|Feb precipitation mm = 47.7
|Mar precipitation mm = 56.9 
|Apr precipitation mm = 79.3
|May precipitation mm = 85.2
|Jun precipitation mm = 92.5
|Jul precipitation mm = 80.4
|Aug precipitation mm = 70.9 
|Sep precipitation mm = 84.1
|Oct precipitation mm = 78.4
|Nov precipitation mm = 79.5
|Dec precipitation mm = 60.0
|year precipitation mm = 871.3
|rain colour = green
|Jan rain mm = 29.0
|Feb rain mm = 26.8
|Mar rain mm = 34.1
|Apr rain mm = 70.6
|May rain mm = 88.1
|Jun rain mm = 89.5
|Jul rain mm = 80.5
|Aug rain mm = 63.5 
|Sep rain mm = 93.3
|Oct rain mm = 77.6
|Nov rain mm = 68.2
|Dec rain mm = 39.0
|year rain mm = 765.2
|snow colour=green
|Jan snow cm = 34.2
|Feb snow cm = 20.2
|Mar snow cm = 22.0
|Apr snow cm = 3.5 
|May snow cm = 0.0
|Jun snow cm = 0.0
|Jul snow cm = 0.0
|Aug snow cm = 0.0
|Sep snow cm = 0.0
|Oct snow cm = 0.5
|Nov snow cm = 7.0
|Dec snow cm = 25.0
|year snow cm = 112.4
|unit precipitation days = 0.2 mm
|Jan precipitation days = 15.2
|Feb precipitation days = 12.0
|Mar precipitation days = 13.2
|Apr precipitation days = 14.1
|May precipitation days = 14.1
|Jun precipitation days = 13.1
|Jul precipitation days = 11.2
|Aug precipitation days = 10.2
|Sep precipitation days = 10.4
|Oct precipitation days = 12.8
|Nov precipitation days = 14.2
|Dec precipitation days = 14.1
|year precipitation days = 154.6
|unit rain days = 0.2 mm
|Jan rain days = 5.9
|Feb rain days = 4.9
|Mar rain days = 7.4
|Apr rain days = 12.7
|May rain days = 13.8
|Jun rain days = 11.4
|Jul rain days = 11.5
|Aug rain days = 10.5
|Sep rain days = 10.4
|Oct rain days = 12.1
|Nov rain days = 11.4
|Dec rain days = 7.1
|year rain days = 119.2
|unit snow days = 0.2 cm
|Jan snow days = 11.7
|Feb snow days = 7.9
|Mar snow days = 7.4
|Apr snow days = 2.5
|May snow days = 0.0
|Jun snow days = 0.0
|Jul snow days = 0.0
|Aug snow days = 0.0
|Sep snow days = 0.0
|Oct snow days = 0.25
|Nov snow days = 3.6
|Dec snow days = 8.4
|year snow days = 41.8
|time day = 0600 LST
|humidity colour = green
|Jan humidity = 82.1
|Feb humidity = 80.9
|Mar humidity = 81.6
|Apr humidity = 81.5
|May humidity = 83.3
|Jun humidity = 85.9
|Jul humidity = 87.9
|Aug humidity = 90.1
|Sep humidity = 89.8
|Oct humidity = 85.3
|Nov humidity = 82.9
|Dec humidity = 83.1
|year humidity = 84.5
|Jan sun = 81.7
|Feb sun = 100.3
|Mar sun = 139.9
|Apr sun = 185.2
|May sun = 236.6
|Jun sun = 266.3
|Jul sun = 299.1
|Aug sun = 254.3
|Sep sun = 191.3
|Oct sun = 151.2
|Nov sun = 87.6
|Dec sun = 67.4
|year sun = 2060.9
|Jan percentsun = 28.0
|Feb percentsun = 33.9
|Mar percentsun = 37.9
|Apr percentsun = 46.2
|May percentsun = 52.2
|Jun percentsun = 58.0
|Jul percentsun = 64.3
|Aug percentsun = 58.9
|Sep percentsun = 50.9
|Oct percentsun = 44.1
|Nov percentsun = 29.9
|Dec percentsun = 24.0
|year percentsun = 44.0
|source 1= [[Environment Canada]]<ref name="CCN">{{cite web |url= https://climate.weather.gc.ca/climate_normals/results_1991_2020_e.html?searchType=stnProv&lstProvince=ON&txtCentralLatMin=0&txtCentralLatSec=0&txtCentralLongMin=0&txtCentralLongSec=0&stnID=199000000&dispBack=0 |title= Sarnia Airport, Ontario |work= Canadian Climate Normals 1991–2020 |date= 31 October 2011 |publisher= [[Environment Canada]] |access-date=23 March 2025}}</ref><ref>{{cite web |url= ftp://ftp.tor.ec.gc.ca/Pub/Normals/English/ONT/ONT_OWEN-WARR_ENG.csv |title= Sarnia Airport, Ontario |work= Canadian Climate Normals 1981–2010 |publisher= [[Environment Canada]] |access-date=9 September 2013}}</ref><ref name = "February 2015">{{cite web |url=http://climate.weather.gc.ca/climate_data/daily_data_e.html?hlyRange=2005-12-07%7C2016-08-05&dlyRange=2006-03-20%7C2016-08-05&mlyRange=%7C&StationID=44323&Prov=ON&urlExtension=_e.html&searchType=stnName&optLimit=yearRange&StartYear=1840&EndYear=2016&selRowPerPage=25&Line=4&searchMethod=contains&Month=2&Day=6&txtStationName=sarnia&timeframe=2&Year=2015 
|title=Daily Data Report for February 2015 
|work=Canadian Climate Data 
|date=31 October 2011 
|publisher=[[Environment Canada]] 
|access-date=6 August 2016}}</ref><ref name = "Sarnia">{{cite web 
|url=http://climate.weather.gc.ca/historical_data/search_historic_data_stations_e.html?searchType=stnName&timeframe=1&txtStationName=sarnia&searchMethod=contains&StartYear=1840&EndYear=2016&optLimit=specDate&Year=1926&Month=11&Day=6&selRowPerPage=25 
|title=Sarnia 
|work=Canadian Climate Data 
|date=31 October 2011 
|publisher=[[Environment Canada]] 
|access-date=6 August 2016}}</ref><ref name = "Sarnia Polysar">{{cite web 
|url=http://climate.weather.gc.ca/historical_data/search_historic_data_stations_e.html?searchType=stnName&timeframe=1&txtStationName=sarnia+polysar&searchMethod=contains&optLimit=yearRange&StartYear=1840&EndYear=2016&Year=2016&Month=8&Day=6&selRowPerPage=25 
|title=Sarnia Polysar
|work=Canadian Climate Data 
|date=31 October 2011
|publisher=[[Environment Canada]] 
|access-date=6 August 2016}}</ref><ref name = "Sarnia Chris Hadfield A">{{cite web 
|url=http://climate.weather.gc.ca/historical_data/search_historic_data_stations_e.html?searchType=stnName&timeframe=1&txtStationName=sarnia+chris+hadfield&searchMethod=contains&optLimit=yearRange&StartYear=1840&EndYear=2016&Year=2016&Month=8&Day=6&selRowPerPage=25 
|title=Sarnia Chris Hadfield A
|work=Canadian Climate Data 
|date=31 October 2011
|publisher=[[Environment Canada]] 
|access-date=6 August 2016}}</ref><ref name = "Sarnia Climate">{{cite web 
|url=http://climate.weather.gc.ca/historical_data/search_historic_data_stations_e.html?searchType=stnName&timeframe=1&txtStationName=sarnia+climate&searchMethod=contains&optLimit=yearRange&StartYear=1840&EndYear=2016&Year=2016&Month=8&Day=6&selRowPerPage=25 
|title=Sarnia Climate
|work=Canadian Climate Data 
|date=31 October 2011
|publisher=[[Environment Canada]] 
|access-date=6 August 2016}}</ref>
|date=March 2012}}