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If you have a Wikipedia account, please log in. </p><p>If you do not have any other way to edit Wikipedia, you will need to <a href="/wiki/Wikipedia:IP_block_exemption#Requesting_and_granting_exemption" title="Wikipedia:IP block exemption">request an IP block exemption</a>. </p> <style data-mw-deduplicate="TemplateStyles:r1214851843">.mw-parser-output .hidden-begin{box-sizing:border-box;width:100%;padding:5px;border:none;font-size:95%}.mw-parser-output .hidden-title{font-weight:bold;line-height:1.6;text-align:left}.mw-parser-output .hidden-content{text-align:left}@media all and (max-width:500px){.mw-parser-output .hidden-begin{width:auto!important;clear:none!important;float:none!important}}</style><div class="hidden-begin mw-collapsible mw-collapsed" style=""><div class="hidden-title skin-nightmode-reset-color" style="text-align:center;">How to appeal if you are confident that your connection does not use a colocation provider's IP address:</div><div class="hidden-content mw-collapsible-content" style=""> If you are confident that you are not using a web host, you may <a href="/wiki/Wikipedia:Appealing_a_block" title="Wikipedia:Appealing a block">appeal this block</a> by adding the following text on your <a href="/wiki/Help:Talk_pages" title="Help:Talk pages">talk page</a>: <code>{{<a href="/wiki/Template:Unblock" title="Template:Unblock">unblock</a>|reason=Caught by a colocation web host block but this host or IP is not a web host. 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Your current IP address is 8.222.208.146. </p> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>Even when blocked, you will <i>usually</i> still be able to edit your <a href="/wiki/Special:MyTalk" title="Special:MyTalk">user talk page</a>, as well as <a href="/wiki/Wikipedia:Emailing_users" title="Wikipedia:Emailing users">email</a> administrators and other editors. </p> </div> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>For information on how to proceed, please read the <b><a href="/wiki/Wikipedia:Appealing_a_block#Common_questions" title="Wikipedia:Appealing a block">FAQ for blocked users</a></b> and the <a href="/wiki/Wikipedia:Appealing_a_block" title="Wikipedia:Appealing a block">guideline on block appeals</a>. 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Review the information below for assistance if you do not believe that you have done anything wrong.<div class="paragraphbreak" style="margin-top:0.5em"></div><div class="paragraphbreak" style="margin-top:0.5em"></div> <p>This block affects editing on all Wikimedia wikis. </p><p>The IP address or range 8.222.128.0/17 has been globally <a href="/wiki/Wikipedia:Blocking_policy" title="Wikipedia:Blocking policy">blocked</a> by <a href="/wiki/User:Jon_Kolbert" title="User:Jon Kolbert">‪Jon Kolbert‬</a> for the following reason(s): </p> <div style="padding:10px; background:var(--background-color-base, white); color:inherit; border:1px #666 solid;"> <p><a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/NOP" class="extiw" title="m:Special:MyLanguage/NOP">Open proxy/Webhost</a>: See the <a href="https://meta.wikimedia.org/wiki/WM:OP/H" class="extiw" title="m:WM:OP/H">help page</a> if you are affected </p> </div> <p>This block will expire on 15:12, 27 August 2028. Your current IP address is 8.222.208.146. </p> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>Even while globally blocked, you will <i>usually</i> still be able to edit pages on <a href="https://meta.wikimedia.org/wiki/" class="extiw" title="m:">Meta-Wiki</a>. </p> </div> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>If you believe you were blocked by mistake, you can find additional information and instructions in the <a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/No_open_proxies" class="extiw" title="m:Special:MyLanguage/No open proxies">No open proxies</a> global policy. Otherwise, to discuss the block please <a href="https://meta.wikimedia.org/wiki/Steward_requests/Global" class="extiw" title="m:Steward requests/Global">post a request for review on Meta-Wiki</a>. You could also send an email to the <a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/Stewards" class="extiw" title="m:Special:MyLanguage/Stewards">stewards</a> <a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/VRT" class="extiw" title="m:Special:MyLanguage/VRT">VRT</a> queue at <kbd>stewards@wikimedia.org</kbd> including all above details. </p> </div> <p>Other useful links: <a href="https://meta.wikimedia.org/wiki/Global_blocks" class="extiw" title="m:Global blocks">Global blocks</a> · <a href="/wiki/Help:I_have_been_blocked" title="Help:I have been blocked">Help:I have been blocked</a> </p> </div></li></ul><hr /> <div id="viewsourcetext">You can view and copy the source of this page:</div><textarea readonly="" accesskey="," id="wpTextbox1" cols="80" rows="25" style="" class="mw-editfont-monospace" lang="en" dir="ltr" name="wpTextbox1">== Definitions == {{Weather}} There are several definitions of heat waves: * The [[Intergovernmental Panel on Climate Change|IPCC]] defines ''heatwave'' as "a period of abnormally hot weather, often defined with reference to a relative temperature threshold, lasting from two days to months."<ref>{{Cite web |title=Heat Waves Explained |date=20 May 2023 |url=https://compass.rauias.com/disaster-management/heat-waves-heat-dome/}}</ref><ref name=":42">IPCC, 2022: Annex II: [https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Annex-II.pdf Glossary] [Möller, V., R. van Diemen, J.B.R. Matthews, C. Méndez, S. Semenov, J.S. Fuglestvedt, A. Reisinger (eds.)]. In: [https://www.ipcc.ch/report/ar6/wg2/ Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, pp. 2897–2930, {{doi|10.1017/9781009325844.029}}.</ref>{{rp|2911}} * A definition based on the ''Heat Wave Duration Index'' is that a heat wave occurs when the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by {{convert|5|C-change|0|lk=on}}, the normal period being 1961–1990.<ref>{{cite journal |last=Frich |first= A. |author2=L.V. Alexander |author3=P. Della-Marta |author4=B. Gleason |author5=M. Haylock |author6=A.M.G. Klein Tank |author7=T. Peterson |date=January 2002 |title=Observed coherent changes in climatic extremes during the second half of the twentieth century |journal=Climate Research |volume= 19 |pages=193–212 |url=http://www.vsamp.com/resume/publications/Frich_et_al.pdf |doi=10.3354/cr019193|bibcode=2002ClRes..19..193F |doi-access=free }}</ref> The same definition is used by the [[World Meteorological Organization]].<ref name=":2">{{Cite web |title=Heat wave meteorology |url=https://www.britannica.com/science/heat-wave-meteorology |access-date=2019-04-01 |publisher=Encyclopedia Britannica }}</ref> * A definition from the ''Glossary of Meteorology'' is:<ref name="Glossary of Meteorology">{{cite book |last=Glickman |first=Todd S. |title=Glossary of Meteorology |publisher=American Meteorological Society |date= 2000 |isbn=9781878220493 }}</ref> "A period of abnormally and uncomfortably hot and usually humid weather." === Definitions by country === ==== Europe ==== Denmark defines a national heat wave (''hedebølge'') as a period of at least 3 consecutive days in which the average maximum temperature across more than half the country exceeds {{convert|28|°C|°F|1}}. The [[Danish Meteorological Institute]] also has a definition for a "warmth wave" (''varmebølge''). It defines this using the same criteria for a {{convert|25|°C|°F|1}} temperature.<ref>{{cite web|url=http://www.dmi.dk/dmi/danmark_faar_varme-_og_hedeboelge |title=Danmark får varme- og hedebølge |language=da |publisher=Danish Meteorological Institute |date=22 July 2008 |access-date=18 July 2013 |url-status=dead |archive-url=https://web.archive.org/web/20080723170544/http://www.dmi.dk/dmi/danmark_faar_varme-_og_hedeboelge |archive-date=23 July 2008 }}</ref> Sweden defines a heat wave as at least five days in a row with a daily high exceeding {{convert|25|°C|°F|1}}.<ref>{{cite web|url=http://www.smhi.se/kunskapsbanken/klimat/varmebolja-1.22372 |title=Värmebölja Klimat: Kunskapsbanken SMHI |language=sv |publisher=Smhi.se |access-date=17 July 2013}}</ref> In Greece, the [http://www.hnms.gr/emy/el/ Hellenic National Meteorological Service] defines a heat wave as occurring over three consecutive days with temperatures at 39 °C (102 °F) or higher. In the same period the minimum temperature is {{convert|26|°C|°F}} or more. During this period, there are either no winds or only weak winds. These conditions occur in a broad area. The Netherlands defines a heat wave as a period of at least five consecutive days in which the maximum temperature in [[De Bilt]] exceeds {{convert|25|°C|°F}}. During this period the maximum temperature in De Bilt must exceed {{convert|30|°C|°F}} for at least three days. Belgium also uses this definition of a heat wave with [[Ukkel]] as a reference point. So does Luxembourg. In the United Kingdom, the [[Met Office]] operates a Heat Health Watch system. This places each Local Authority region into one of four levels. Heat wave conditions occur when the maximum daytime temperature and minimum nighttime temperature rise above the threshold for a particular region. The length of time above that threshold determines the level. Level 1 represents normal summer conditions. Level 2 occurs when there is a 60% or higher risk that the temperature will be above the threshold levels for two days and the intervening night. Level 3 arises when the temperature has been above the threshold for the preceding day and night, and there is a 90% or higher chance that it will stay above the threshold in the following day. Level 4 is triggered if conditions are more severe than those of the preceding three levels. Each of the first three levels gives rise to a particular state of readiness and response by the social and health services. Level 4 involves a more widespread response.<ref>{{cite web |date=31 August 2011 |title=Heat-health watch |url=http://www.metoffice.gov.uk/public/weather/heat-health/ |access-date=17 July 2013 |publisher=Met Office}}</ref> The threshold for a heat wave occurs when there are at least three days above {{convert|25|°C|°F}} across much of the country. Greater London has a threshold of {{convert|28|°C|°F}}.<ref>{{cite web |date=26 May 2023 |title=What is a heatwave?|url=https://www.metoffice.gov.uk/weather/learn-about/weather/types-of-weather/temperature/heatwave |access-date=26 May 2023 |publisher=Met Office}}</ref> ==== Other regions ==== In the United States, definitions also vary by region. They usually involve a period of at least two or more days of excessively hot weather.<ref>{{cite web |url=http://www.weather.gov/glossary/index.php?word=heat+wave |title=Glossary |publisher=NOAA's National Weather Service |date=25 June 2009 |access-date=17 July 2013}}</ref> In the [[Northeastern United States|Northeast]], a heat wave is typically when the temperature reaches or exceeds {{convert|90|°F|°C|1}} for three consecutive days. This is not always the case. This is because the high temperature ties in with humidity levels to determine a heat index threshold.<ref>{{cite web |last=Singer |first=Stephen |title=Half the country wilts under unrelenting heat |url=http://old.news.yahoo.com/s/ap/us_hot_weather |publisher=Yahoo! News |url-status=dead |archive-url=https://archive.today/20120716024044/http://old.news.yahoo.com/s/ap/us_hot_weather |archive-date=16 July 2012 |df=dmy-all}}</ref> The same does not apply to drier climates. A heat storm is a Californian term for an extended heat wave. Heat storms occur when the temperature reaches {{convert|100|°F|°C|1}} for three or more consecutive days over a wide area (tens of thousands of square miles).<ref>{{cite web|title=Staying Cool and Safe|publisher=[[Pacific Gas and Electric Company]]|location=Oakland, California|date=24 March 2017|accessdate=26 June 2023|url=https://www.pge.com/includes/docs/pdfs/myhome/edusafety/seasonal/coolingcenters/staying_cooling_and_safe_english.pdf|archive-date=27 June 2023|archive-url=https://web.archive.org/web/20230627064913/https://www.pge.com/includes/docs/pdfs/myhome/edusafety/seasonal/coolingcenters/staying_cooling_and_safe_english.pdf|url-status=dead}}</ref> The [[National Weather Service]] issues [[heat advisory|heat advisories]] and [[excessive heat warning]]s when it expects unusual periods of hot weather. In Adelaide, South Australia, a heat wave is five consecutive days at or above {{convert|35|°C|°F}}, or three consecutive days at or over {{convert|40|°C|°F}}.<ref>{{cite web |url=http://www.bom.gov.au/announcements/media_releases/sa/20100115_First_Heatwave_SA_Jan.shtml |title=Extreme Heat Services for South Australia |publisher=Bureau of Meteorology |date=15 January 2010 |access-date=17 July 2013}}</ref> The [[Bureau of Meteorology|Australian Bureau of Meteorology]] defines a heat wave as three or more days of unusual maximum and minimum temperatures.<ref name=":0">{{Cite web|title = Australia Weather and Warnings|url = http://www.bom.gov.au/weather-services/about/heatwave-forecast.shtml|publisher = Bureau of Meteorology|access-date = 2016-01-17|language = en|archive-date = 16 October 2015|archive-url = https://web.archive.org/web/20151016140923/http://www.bom.gov.au/weather-services/about/heatwave-forecast.shtml|url-status = dead}}</ref> Before this new Pilot Heatwave Forecast there was no national definition for heat waves or measures of heat wave severity.<ref name=":0" /> </textarea><div class="templatesUsed"></div><p id="mw-returnto">Return to <a href="/wiki/Heat_wave" title="Heat wave">Heat wave</a>.</p> <noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; 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