![Heatwave](https://i.guim.co.uk/img/media/2586dd3317e2a633d3271fce867e2c96dbec9bd8/0_0_6409_4273/master/6409.jpg?width=1140&dpr=2&s=none)
The scorching heatwave that has swept the US south-east in recent weeks will soon spread to the country’s midwest and north-east regions, affecting nearly 250 million Americans.
Temperatures are stuck at 90F (32C) or above for at least the next week in much of the US, the National Weather Service (NWS) predicted. The NWS defines a heatwave as a period of temperatures exceeding 90F for two or more days, and this one could last until 26 June.
The NWS said: “The first heatwave of the summer begins Sunday over the middle of the nation, before spreading to the midwest and to the north-east by Tuesday then lasting most of next week,” with temperatures expected to approach 105F and break records, with very warm nights.
Soon, cities including Chicago, Indianapolis, Cleveland, Pittsburgh, Philadelphia and Boston may also see their hottest day of the year so far. And humidity is likely to be high.