A number of heatwaves began across parts of the northern hemisphere in April 2023, many of which are ongoing. Various heat records have been broken,^[1] with July being the hottest month on record.^[2] The abnormal temperatures have led to a "very extreme" liklihood of wildfires, according to the Fire Weather Index.^[3] Scientists have attributed the heat waves to man-made climate change.^[1][2] During each day in July 2023, 2 billion people experience heat conditions made at least three times more likely due to climate change and 6.5 billion people experienced this impact at least one day in this month. The heatwaves caused severe damage in southern USA, Southern Europe, South and southeast Asia.^[4]

On 1st August 2023 the average sea surface temperature reached 20.96 °C (69.73 °F), the highest ever recorded. Scientists worry how warm the oceans will be next March, as March is when oceans are warmest. ^[5]

A three-day heatwave originating in North Africa took place from 26 to 28 April, impacting the Western Mediterranean region. The heat reached over 40°C in parts of Morocco and Algeria.^[6]

Morocco, Algeria and Tunisa still had temperatures of up to 47 °C (117 °F) on July 13.^[7]

A heat wave hit Tabarka, Tunisia, on July 14.^[8][9]

18 July recorded data was-

1. Tozeur, Tunisia, 46.9 °C (116.4 °F).^[10]
2. Chlef, Algeria 47.4 °C (117.3 °F) and many other places in excess of 44°C (111°F).^[10]
3. Faya, Chad 45.8 °C (114.4 °F) ^[10]
4. Kharga in Egypt 45.2°C (113°F). ^[10]
5. Bilma, Niger 44.4°C (112°F).^[10]

A week of power cuts and 40 °C (104 °F) temperatures in Cairo had occurred by July 19.^[11]

Starting in April 2023, a record-breaking heat wave in Asia has affected multiple countries, including India, China, Laos and Thailand.^[12][13]

Turkmenistan recorded 42 degrees Celsius (107.6 Fahrenheit) on the 26th.^[14]

The head of the Ministry of Emergency Situations, Alexander Kurenkov, traveled to the fire hit Kurgan Oblast on 26 April.^[15]

The European Union’s Copernicus Atmosphere Monitoring Service said on 26 April that fires started in May continue to burn from Russia’s Chelyabinsk, Omsk and Novosibirsk Oblats, Primorye Krai, Kazakhstan and Mongolia.^[15]

80 fires were active over an area of 113,500 hectares (280,000 acres) in the regions of the Ural Federal District on 8 May.^[15]

Over 43 degrees Celsius (109.4 degrees Fahrenheit) was recorded in Uzbekistan on 31 May. ^[14]

Over 41 degrees Celsius (105.8 degrees Fahrenheit) was recorded in Kazakhstan on 31 May.^[14]

Over than 45 degrees Celsius (111.2 Fahrenheit) was recorded in China on 31 May.^[14]

A heat wave in early June in Israel, with temperatures between 35°C (95°F) in Jerusalem and 45°C (113°F) in the Jordan Valley, along with high winds, caused hundreds of bushfires. Roads and some buildings were evacuated amid rolling electricity outages on the 2nd. Firefighters quickly controlled the fires, limiting property damage.^[16]

37.9 degrees Celsius (100.2 Fahrenheit) in Jalturovosk on 3 June.^[14]

8 June data was recorded at^[14]-

1. 38.0 °C (100.4 °F) Zdvinsk
2. 35.6 °C (96.1 °F) Tomsk tie
3. 38.0 °C (100.4 °F) Verkhoyansk
4. 38.2 °C (100.8 °F) Kupino
5. 36.7 °C (98.1 °F) Kolyvan
6. 36.3 °C (97.3 °F) Ermakovskoe
7. 35.3 °C (95.5 °F) Tastyp

Beijing hit 40 °C (104 °F) on the 6th after 10 days of above 35 °C (95 °F). The government ordered all employers to stop any outdoor work and for people to work from home if they could.^[17]

It was revealed on 8 June that the wildfires in Russia’s Ural Mountains during May had killed at least 21 people.^[14]

Parts of Mongolia recorded 30 °C (86 °F), especially in eastern steppe and southern Gobi provinces, with a prediction of 38 °C (100 °F) for the 21st, in the Khanbogd soum. ^[18]

Heatstroke claimed 22 lives in Mardan, Islamabad on 26 June and temperatures rose above the seasonal average ^[19]

On 11 July 2023 in Yekaterinburg (56° north latitude) in Russia for the first time in the history of meteorological observations (more than 187 years), a temperature of +40 °C (104 °F) was recorded.^[20]

On 16 July 2023, China recorded a record-breaking temperature of 52.2 °C (126.0 °F).^[21]

The Japanese government and NHK issued health advice to the general public as heatstroke alerts for 20 of the country’s 47 prefectures, mostly east and southwest on 16 July.^[22]

16 July data was recorded as:^[22]

1. Kiryu city in Gunma prefecture, hit 39.7C.
2. Hachioji in western Tokyo hit 38.9C,.
3. Hirono town in Fukushima prefecture hit 37.3C.
4. Nasushiobara with 35.4C.

Torrential rain poured down in northern Japan, causing floods and 1 resultant landslide on 16 July.^[22]

Al Ahsa, Saudi Arabia recorded 50.5°C (122.9°F) on 18.^[10]

The Korea Meteorological Administration (KMA) issued a heat wave warning on the 19th and warned people to expected temperatures of 33 C for the foreseeable future, with southern Gangwon Province, North Chungcheong Province and some southern regions to see some rain which was expected to be about 5 to 20 millimeters in total depth on the 19th.^[23]

On the 20th a heatwave is declared in Mongolia after temperatures of 38 °C (100 °F) continue in the Khanbogd soum.

Japan's government and Fire and Disaster Management Agency responded to the ongoing excessive heat by issuing more heath advisory notices to the public on 19 July. The Fire and Disaster Management Agency's official weekly statistics for 19 July showed 8,189 (4,484 were 65 or over) were hospitalized that week, up 200% on the previous week and that time in 2022. Tokyo had the highest number with 1,066, up 460% on 2022. 3,215 got heatstroke at home 1,445 got it outside nationwide. 3 people had also died that week as the heat reached 39C in many parts of Japan on 19 July. ^[24]

South Korea and China had reported deadly floods due to unusually heavy rains, leaving several dozen people dead on the 23rd. ^[25] The record heat continued in Japan and Korea on the 23rd. ^[25]

The remnants of Typhoon Doksuri hits Hebei province and Beijing, killing 21 people as it did so. 744.8 millimeters (29.3 inches) of rain fell on Beijing between July 26 and August 2nd according to the Beijing Meteorological Bureau as Beijing and the province of Hebei had floods that destroyed roads, knocked out power and cut water pipes. Zhuozhou, in Hebei was so badly hit that local police messaged a plea on Weibo for lights to assist rescue workers in the devastated city.^{[26][27][28][29][30][31]}

It was 35C at Seoul, S. Korea on August 4th.^[32]

Europe broke its temperature record for April when the air at Córdoba Airport reached 38.8 °C (101.8 °F).^[6][33] On 26 April, a Sentinel-2 image showed that the Fuente de Piedra Lagoon went completely dry for the first time.^[34] A rapid attribution study by World Weather Attribution found that the heatwave would probably have been more than 2°C cooler without climate change and that climate change made the heat wave 100 times more likely to occur.^[35]

Northern Norway's Slettnes Lighthouse, reached 28.8 °C (83.8 °F) on 13 July^[36]

A major extended heatwave affecting most of Europe through mid-July was named "Cerberus" by the Italian Meteorological Society^[37] and brought record temperatures into the Arctic.^[38]

On July 18, temperatures reached as high as:^[39]

1. Sardinia 47 °C (117 °F)
2. Rome 41.8 °C (107.2 °F)
3. Athens 41 °C (106 °F)
4. Santorini 41 °C (106 °F)
5. Seville 41 °C (106 °F)
6. Madrid 37 °C (99 °F)

A forest fire hit La Palma on 22 that led to 500 people being evacuated.^[25]

Bush fires hit Rhodes on 22 and 23.^[40]

Bush fires hit Lardos and Kiotari, Greece on 23. Rhodes was 49 °C (120 °F) on the 23rd, with the evacuation of tourists starting that day. 8 EU countries send firemen to help Greece, while Israel, Jordan and Turkey sent mostly aerial equipment to the Greek fire brigade. ^[40]

16 Italian cities were under red alerts for heat, including Rome, Florence and Bologna on 23. ^[25]

Wildfires hit Turkey, Bulgaria, Croatia, Albania, N. Macedonia, Greece and southern Italy on the 26th and 27th. ^[41]

The 27th saw wild fires in and around Sicily, Dubrovnik, Rhodes, Gran Canaria, Lisbon and Cascais in Portugal. ^[42][43]

It was 40ºC. around Zaporizhzhia and lake in Sloviansk on August 5th.^[44]

30cm of hail fell on the German city of Reutlingen on the 5th. ^[45]

Arviat, Nunavut recorded 21.2 °C (70.2 °F) on 13 May.^[46]

An intense heat wave impacted Puerto Rico and the Caribbean in early June, bringing record highs to San Juan and causing the heat index to reach 125 °F (52 °C) in one town.^[47]

In Mexico, a heat wave swept northern states, such as Sonora where temperatures were recorded as high as 49°C (120°F).^[48] Over 100 people died from heat stroke or dehydration.^[49]

In the United States, "an extreme heat wave" affected many states including Texas, New Mexico, Arizona, Nevada, and California. Temperatures reached as high as 53°C (128°F) in Death Valley while Phoenix, AZ saw 48°C (119°F) and broke the record of 18 consecutive 110+ temperature days recording 31^[50] consecutive days above 110F.^[51] Heat warnings were issued across many southern states as far east as Florida.^{[citation needed]}

July 31st saw the Eagle Bluff Fire trigger the evacuation of Osoyoos, British Columbia^[52] as temperatures hit 30C.^[52] Both US and Canadian officials estimated that around 2,200 acres (3.44 square miles) on the Canadian side of the border and around 2,000 acres (3.13 square miles) on the US side of the border were on fire.^[52] 1 firefighter died on the Canadian side.^[52] 1,500 blazes were burning in Washington State and British Colombia that day and 101 are out of control.^[52]

California's week old York Fire was the state's biggest that year by August 1st, at over 125 square miles (323.7 square kilometers) and was 23% contained according to Californian fire officials.^[53] About 400 firefighters were fighting the blaze and had to balance their efforts with concerns about disrupting the fragile ecosystem in California's Mojave National Preserve.^[53]

Oklahoma has seen multiple times where the heat index has reached 115 °F (46 °C). Also more extreme heat on August 4 in Texas.

In August 2023 a heat wave hit South America, leading to temperatures in many areas above 95 °F (35 °C) in midwinter. Some locations set all-time heat records.^[54]

China’s top diplomat Wang Yi and American diplomat John Kerry called for “global leadership” on climate issues.^[55]

Some meteorological scientists officially blamed climate change for the event.^[25]

On August 2, Xi Jinping, General Secretary of the Central Committee and the president of the People's Republic of China, urged local officials to make every effort to find the 29 individuals who are missing and the may people who were trapped rising flood waters.^[56]

• Weather of 2023
• 2023 Asia heat wave
• 2023 European heat waves
• 2023 Western North America heat wave