Residents of US south-west swelter under record-breaking heatwave

Relentless temperatures upwards of 100F leave millions under extreme heat warnings and outdoor events cancelled

Record-breaking heat is baking the US south-west this week, putting millions under extreme heat warnings as temperatures upwards of 100F (38C) hit Arizona, Nevada, New Mexico and southern California for days on end.

Even desert residents accustomed to scorching summers are feeling the relentless grip of the heat. Phoenix, which hit a 12th consecutive day of 110F on Tuesday, could see its longest ever heatwave.