Texas cities have reached an unprecedented heat index – which combines temperature and humidity. Corpus Christi has hit 125F (51C), while Rio Grande Village notched 118F (47C) and Del Rio marked 115F (46C). States including New Mexico, Louisiana, Arkansas, Kansas and Missouri are also experiencing scorching heat, with the National Weather Service predicting the temperatures to rise further and last into the week of 4 July.
The heat follows a weekend of destructive storms that left hundreds of thousands of people without power. The heat dome, as it is known, has settled above Mexico and parts of the US south-west and is caused by hot ocean air that has become trapped in the atmosphere.