As the world sweltered through the hottest three month spell in human history this summer, extreme weather disasters took more than 18,000 lives, drove at least 150,000 people from their homes, affected hundreds of millions of others and caused billions of dollars of damage.
That is a conservative tally from the most widely covered disasters between early June and early September, which have been compiled in the timeline below as a reminder of how tough this period has been and what might lie ahead.
June
Haiti
2 June
Misery added to poverty

Unusually intense rains flood towns and villages, killing 42 and destroying more than 10,000 homes.
Canada
7 June
Fires the size of Greece

Smoke from devastating wildfires in Quebec casts a pall over New York and prompts air quality warnings for tens of millions of people. Over the course of the summer, fires across Canada would go on to burn 17.9m hectares of land, double the previous record. At least six people are killed and thousands evacuated. “The word ‘unprecedented’ doesn’t do justice to the severity of the wildfires in Canada this year,” said Yan Boulanger of Natural Resources Canada. “From a scientific perspective, the doubling of the previous burned area record is shocking.”
The area burned by wildfires in Canada so far this year is more than seven times the yearly average
20m cumulative hectares burned
7 Jun 2023
4.1m ha
close to the size
of Denmark
27 Sep 2023
17.9m ha
close to the
size of Syria
15
10
2003-22
5
2003-22
average
2.4m ha
0
May
Jun
Jul
Aug
Sep
The area burned by wildfires in Canada so far this year is more than seven times the 2003-22 average
20m cumulative hectares burned
27 Sep 2023
17.9m ha
close to the
size of Syria
15
7 Jun 2023
4.1m ha
close to the size
of Denmark
10
2003-22
5
2003-22
average
2.4m ha
0
May
June
July
August
September
Iran
9 June
Killer gales and severe droughts
Severe wind and rain kill seven people and injured 59 in the northwest regions. Authorities later report 97% of the country is experiencing water shortages amid a persistent drought.
Balkans
20-23 June
Hailstones the size of cannonballs and flash floods
A supercell brings hailstones,up to 14cm in diameter, to Slovenia and Croatia, destroying crops and tearing the roofs off houses. At least three people die in flash floods in Kosovo and Romania. “A catastrophe of this magnitude has never been recorded here before,” says the council head of the worst affected Romanian region, Arad County. Serbia declared an emergency in Belgrade and 50 other municipalities. Thousands of homes are damaged.
Antarctic
28 June
Texas-sized decline in sea ice
Sea ice in the southern hemisphere drops 1.2m sq km (roughly the size of Texas) below the previous record low for early winter. Monthly records follow for July and August.
Antarctic sea ice extent, 28 June 2023
Sea ice extent
28 June 2023
June av 1981-2010
June av each year 2000-22
Ice shelves
0º
Southern
Ocean
Weddell
Sea
Antarctica
Ronne
South Pole
90º
W
90º
E
Ross
Antarctic
Circle
Ross
Sea
Southern
Ocean
180º
Antarctic sea ice extent, 28 June 2023
Antarctic sea ice extent, 28 June 2023
Sea ice extent
0º
28 June 2023
June av 1981-2010
June av each year 2000-22
Southern
Ocean
Ice shelves
Weddell
Sea
South
America
Antarctica
Ronne
South Pole
90ºW
90ºE
Ross
Ross
Sea
Antarctic
Circle
Southern
Ocean
180º
The annual maximum extent of Antarctic sea ice in 2023 was 1m sq km below the previous record low
Area of ocean with at least 15% sea ice, million sq km
20
All years 1979 to present
1991-2000 average
15
2022
27 Sep 2023
16.6m sq km
10
28 Jun 2023
11.8m sq km
5
0
1 Jan
1 Apr
1 Jul
1 Oct
31 Dec
20
All years 1979 to present
15
1991-2000 average
27 Sep 2023
16.6m sq km
2022
10
28 Jun 2023
11.8m sq km
5
0
1 Jan
1 Apr
1 Jul
1 Oct
31 Dec
South Africa
29 June
Tornado in the southern winter
Seven people die in heavy rain and wind, followed by a tornado in KwaZulu-Natal. Officials in Durban said: “We are experiencing first hand the true effects of climate change during the winter season.”
July
India and Pakistan
5-16 July
The longest-lasting tropical cyclone in the Arabian Sea

Cyclone Biparjoy (which means “calamity”) wreaks havoc for 10 days, killing 12 people in India, injuring 12 and forcing the evacuation of 81,000 people in Pakistan. This came amid a devastating monsoon season. New Delhi endured its wettest July day (9 July) in 40 years with 153mm of rain. A landslide in Raigad kills at least 16 with more than 100 feared missing under debris.
China
7 July
Air raid shelters converted into heat refuges
Beijing suspends outdoor work after a tour guide in the Summer Palace collapses and dies on the ninth straight day of temperatures over 35C. Hangzhou and Shijiazhuang open air raid shelters as refuges from the heat. Energy companies say they are burning record amounts of coal to meet the demand for air conditioning.
Japan
10 July
‘Heaviest rain ever’
Six people die in Kyushu during floods and landslides. Meteorological officials describe the deluge as the “heaviest rain ever”.
Italy
12 July
Road worker collapses in the street and dies

A 44-year-old road marking painter collapses on the street and dies from heat stress in Lodi, south-east of Milan, as temperatures soar above 40C in Europe’s Cerberus heatwave.
Pakistan
9 July
Grief at monsoon death toll
Monsoon rains lash Lahore and other regions, taking the toll since June to 76 deaths and 133 injuries.
Israel
15 July
Prime minister taken to hospital with dehydration
The Israeli prime minister, Benjamin Netanyahu, is rushed to hospital with suspected dehydration following a day spent in the sun without a hat or water.
China
16 July
All-time heat record shattered
An all-time China temperature record of 52.2C is set in Sanbao, exceeding the previous high by almost two degrees.
Temperature estimates on 16 July, 1900 GMT
-10C
0
10
20
30
40
50
Sanbao, Xinjiang 52.2C China heat record
Pacific
Ocean
Tibetan
Plateau
Indian
Ocean
-10C
0
10
20
30
40
50
Arctic Ocean
Sanbao, Xinjiang 52.2C China heat record
Pacific Ocean
Tibetan
Plateau
Indian Ocean
US
17 July
Death Valley sets world midnight temperature record

Death Valley records the highest midnight temperature in world history of 48.9C as heat tourists flock to the area.
Mexico
16 July
Surge in heat deaths
The government reports 167 deaths from extreme heat since March, dozens more than the previous year. This comes amid a record-long and wide heatwave that sees temperatures rise to 42C in the Valles Centrales and other areas.
US
16 July
Broken air conditioner proves fatal in record heatwave
A Texan man dies after suffering heat stroke when the air conditioner breaks down in his Harris County home amid extreme temperatures in the southern US. The protracted heatwave stretching from Florida to California breaks 2,300 temperature records, takes dozens of lives and affects close to 100 million people.
Algeria
16 July
Fainting in the road
A 55-year-old man in Relizane dies amid a record heatwave, with temperatures over 50C paralysing outside activity after 10am. About 50 people are taken to hospital after fainting on the street, according to local media.
USA
17 July
Fatal flash floods

After days of heavy rain, flash floods sweep across swathes of the US’s north-east, killing at least seven people in Pennsylvania and one in New York, flooding roads, cutting electricity supplies and forcing the cancellation of nearly 1,500 flights.
Spain
17 July
Crisis declared in the olive oil industry
A heatwave and record temperatures in parts of the country (Catalonia records its hottest day with temperatures of 45.3C) scorch crops, leading annual production forecasts to be more than a third below average for the second consecutive year. Extreme weather also threatens rice production in Asia and soy production in the US and South America.
Italy
18 July
Hospitals adopt Covid-style protocols
Medical institutions enter emergency mode to cope with a rise in emergency cases related to heat-stress as temperatures across the country soared to historic highs. Rome bakes in 41.8C, smashing the city’s previous record set last year by more than a degree. In Sardinia, the mercury rose to 45C.
Greece
23 July
Biggest wildfire evacuation in history

More than 20,000 people are relocated from Rhodes as swathes of the island are engulfed by fire. Greece suffers the longest and most intense heatwave in the country’s history. A national record of 46.4C is set at Gytheio, and Athens is so hot that authorities close the Acropolis at midday.
Italy
24 July
Hailstones damage jetliner wings
A Delta Air Lines flight is forced to make an emergency landing in Rome after its wings are damaged by giant hailstones during a supercell storm in northern Italy. In Lombardy, two people are killed by falling trees.
South Korea
25 June to 26 July
Dozens killed in torrential rains
Forty-seven people are killed in the country’s third most intense monsoon season on record.
China
26-30 July
Beijing’s most intense downpour in history
Floods in the capital kill 44 people. Dozens more die across northern China as some areas received a year’s worth of rain in one week. The economic damage is estimated at more than $2bn. Two weeks after this, a mudslide in Xi’an buries 21 people and forces the evacuation of 17,000 after the consecutive typhoons Khanun and Doksuri.
Russia
July 30
Storm causes campsite carnage
Eight campers are killed and 27 are injured in a fierce storm in Mari El on the bank of the Volga River that brings trees down onto the tents.
July 2023 was the world's hottest month on record
Monthly average global surface temperature anomalies relative to a 1991-2020 baseline
Cooler than avearge
Warmer than avearge
30 hottest months on record
+0.8C
July and August 2023
1st and 2nd hottest
months on record,
June was 8th hottest
+0.4
July 1998
22nd hottest
0
-0.4
-0.8
1980
1990
2000
2010
2020
Monthly average global surface temperature anomalies relative to a 1991-2020 baseline
Cooler than avearge
Warmer than avearge
30 hottest months on record
+0.8C
July 1998
22nd hottest month
on record
+0.4
0
July and August 2023
1st and 2nd hottest
months on record,
June was 8th hottest
-0.4
-0.8
1980
1985
1990
1995
2000
2005
2010
2015
2020
August
UK
4 August
Europe Heatwave costs world 0.6% of GDP
A study by the Allianz insurance company estimates the heatwaves of the previous three months cost the world 0.6% of GDP in lost working hours, even without calculating the greater effects on health, infrastructure and agricultural production. Separately, other insurance companies appear to be reducing their exposure to climate risks by raising premiums and denying cover in areas at high risk of wildfires and storms.
Chile
5 August
Off-the-charts winter heat record in Andean mountains
Freakish winter heat above 37C in the Andean mountains of South America prompts meteorologist to declare: “This event is rewriting all climatic books.”
Slovenia and Georgia
6 August
Deaths after record rain
A month’s worth of rain in just 24 hours soaks Slovenia, killing three and causing an estimated €500m of damage. Nineteen die in a mudslide in the Shovi region of Georgia.
Hawaii
8 August
Deadliest wildfire in US history

An uncontrolled blaze kills at least 97 in Lahaina on Maui island. A drier than usual summer had created tinderbox conditions in an area where fire-resistant native vegetation had long ago been replaced by sugarcane plantations and invasive grasses.
Nepal
8 August
High mountains no refuge from deadly rains
The government announces that landslides and floods during this year’s monsoon have killed 38 people, destroyed countless homes and blocked a major highway.
Greece
22 August
18 migrants killed in EU’s biggest fire
The corpses, including those of two children, found in Dadia national forest are among 21 victims of the biggest wildfire in the EU since records began. Even the local hospital at the regional capital of Alexandroupoli has to be evacuated. Dozens of other fires erupted throughout the summer. A month earlier, 20,000 people, including holidaymakers, were rescued from fires on the island of Rhodes in what was described as the biggest evacuation in modern Greek history.
US
23 August
Morgues run out of space for bodies during record heatwave
Morgues in Maricopa County, Arizona order extra coolers after a record 44 heat related deaths in one week. The previous month, Phoenix endured daily highs over 43.3C (110F) for 31 days in a row (smashing the record of 17 days from 1974).
US
22 August
Hilary smashes state rainfall records
Nevada’s daily rainfall record is doubled during Tropical Storm Hilary, which also set records in Idaho, Montana and Oregon. It had previously swept through Mexico, killing one man, and deluged California.
Tajikistan
28-30 August
Central Asia’s deadly downpour
Three days of torrential rain near the capital caused floods, landslides and mudflows that kill at least 21 people in the central region near Dushanbe.
US
30 August
Heatstroke blamed for record number of migrant deaths
The number of migrant deaths in El Paso hits a record annual high of 136, largely due to extreme heat, according to a US Border Patrol report. This is almost double the figure for the entirety of last year. “Migrants have told us they are being held without sufficient food or water on the Mexican side, or they were waiting for hours in the desert for the opportunity to cross,” said one official.
…And the catastrophe goes on inSeptember
Brazil
5 September
‘Worst ever’ climate catastrophe in southern state

The governor of Rio Grande do Sul says his state has suffered its worst ever death toll due to a climate event after an extratropical cyclone kills 31 and leaves over 1,600 homeless.
Hong Kong
8 September
Heaviest rain since records began
The most intense downpour in 140 years kills two and injures more than 100 as Typhoon Haikui sweeps across southern China.
Libya
9-11 September
World’s deadliest weather event of the year.
More than 11,300 people are killed in flooding in the coastal city of Derna after record rainfall leads to the collapse of dams. In a single day, Storm Daniel unleashed 200 times as much rain as usually falls on the city in the entire month of September. Human-induced climate change made this up to 50 times more likely.
Heatwaves, fires, floods and storms occur every year, but their intensity is being steadily amplified by human-caused climate disruption, and in 2023, given an extra boost by an El Niño. Scientists have examined a selection of these events and found human emissions massively loaded the dice in favour of disaster.
The final death toll from these months is likely to be far higher than the casualty figures reported at the time because excess heat deaths take many months to calculate.
It is also a taste of more to come. This summer’s heatwave – or worse – is forecast to occur two out of every five years if global heating reaches 2C above pre-industrial levels, and the world is currently on course to go much higher in the coming decades.