Ferocious heat dome is set to shatter hundreds of weather records with sweltering heat and humidity that will last for a week

A record-breaking heatwave is suffocating the US with sweltering temperatures and thick humidity set to last for a week.

Over 270 million Americans will be hit by temperatures of at least 90 degrees this week, with extreme heat warnings put in place for swathes of the country. 

The spike is due to a heat dome which has settled over the East, trapping in hot air while the sun continually shines, making every day hotter than the last. 

Hundreds of records are set to be broken this week as parts of the Midwest and Northeast endure the longest heat wave they have seen in decades. 

Heat related illnesses are a serious concern in severely impacted areas with the electrical grid under strain and the elderly, children and outdoor workers warned to be particularly careful. 

A record-breaking heatwave is suffocating the US with sweltering temperatures with high humidity making it feel even hotter than it is

Forecasters have put extreme weather warnings for swathes of the country from the Great Lakes into the Northeast

The weather is set to break all-time temperature records for June this week reaching levels normally not seen until the hottest days of July. 

Desperate residents have flocked to beaches and fountains seeking respite from the unseasonal warmth.  

Americans as far North as Maine will be hit by the sweltering heat well into the 90s this week. 

And it will feel even hotter than the thermometer reads as humidity drives heat index values into the 100s. 

Forecasters have put extreme weather warnings for swathes of the country from the Great Lakes into the Northeast. 

Wednesday and Thursday are set to be the hottest days but only marginally. 

Several major cities will be dangerously hot including Chicago, Detroit, Cleveland Pittsburgh, New York and Boston. 

Over 270 million Americans will be hit by temperatures of at least 90 degrees this week, with extreme heat warnings put in place for swathes of the country

The spike is due to a heat dome which has settled over the East, trapping in hot air while the sun continually shines, making every day hotter than the last

The heat wave started on Monday with temperatures jumping 15 degrees above normal in the afternoon and staying high overnight. 

They are set to rise a further 25 degrees above normal through the rest of the week. 

Some of the worst affected areas like Pittsburgh haven't seen such hot weather in over 30 years.  

The local Pittsburgh weather service said on X: 'Last time we saw heat in Pittsburgh like what we’re expecting next week was 30 yrs ago (almost to the day) when it reached 95°F or warmer for 6 straight days (June 15-20, 1994).

'That stands as the longest stretch of 95+ (degree) days on record. We have a shot at tying or beating that.'

New York, Burlington and Cleveland are all opening cooling centers for the week to help residents handle the heat. 

Outdoor workers will be given cooling kits. 

The heat wave started on Monday with temperatures jumping 15 degrees above normal in the afternoon and staying high overnight

Some of the worst affected areas like Pittsburgh haven't seen such hot weather in over 30 years

Heat domes work by trapping hot air in place above an area.

The sun then continually warms the air and without circulation it gets hotter and hotter each day. 

The oven-like conditions mean it doesn't get cold enough overnight to offer people relief, raising the risk of heat-related illnesses. 

The Weather Prediction Service said: 'Warm overnight temperatures only dropping into the mid-70s will offer little to no relief, especially to those without adequate or reliable cooling.' 

High humidity will make it feel even hotter than it is with people warned to limit outdoor activity, stay hydrated and check on neighbors.