Extremely hot weather has started to hit most of the United States, with temperatures set to peak over the weekend, meteorologists say.The heatwave could affect about 200 million people in major cities like New York, Washington and Boston in the East Coast, and the Midwest region too.
In some places, temperatures could be close to or exceed 100F (38C). Parts of Canada are also being hit.
Experts link more frequent heatwaves in recent years to climate change.
The world experienced its hottest June on record this year, with an average temperature worldwide of 61.6F (16.4C), according to new data.
Earlier this month, the US state of Alaska, part of which lies inside the Arctic Circle, registered record high temperatures.
The heatwave is hitting an area stretching from the Central Plains of Colorado and Kansas, to the Great Lakes in the north-east.Temperatures are also rising in most areas of the East Coast. The National Weather Service (NWS) published a map of the areas that are affected.