A blistering US heatwave is set to intensify, with warnings issued across the southwest up to Washington state.

Around 27 million people across the US will feel temperatures over 110F (43C) in the coming days, the National Weather Service (NWS) forecasted.

In Texas, air conditioner use has led the state to surpass its previous record for power consumption as people try to keep cool.

The NWS has cautioned that this intense July heatwave could be dangerous.

Much of the southwestern US is under a heat advisory as of Friday, from Florida to Texas to California, impacting at least 93 million Americans.

The heat is a result of an upper level ridge of high pressure, which typically brings with it warmer temperatures, the NWS said.

The agency added it is “one of the strongest” systems of its kind that the region has ever seen.

“The subtropical ridge responsible for this likely historic heatwave across the region is not showing signs of letting up anytime soon,” the NWS said.

About 700 people are estimated to die each year from heat-related causes in the US, according to the Centers for Disease Control and Prevention.

Both Friday and Saturday will be exceptionally hot, with daytime highs forecasted to hit up to 115F (46C). For some areas, the scorching heat is expected to linger until next week.

The heatwave is impacting states that are typically hot during the summer, but multiple regions are projected to match or surpass their all-time high heat records.

Las Vegas may match its all-time high of 117F (47C) in the next few days, while Death Valley, California - one of the hottest places on earth - could surpass its official all-time high temperature of 130F (54C).

Parts of the southwestern US were already grappling with intensely hot temperatures over the last week. In El Paso, Texas temperatures have been in the triple-digits Fahrenheit for 27 consecutive days.

Overnight temperatures are expected to remain “abnormally warm” in some areas, offering little night-time relief from the heat.

Demand for power in the southern US state has surpassed record numbers for two days in a row because of the heat.

The Electric Reliability Council of Texas (ECROT), which manages 90% of the power load in Texas, said its usage hit a preliminary 81,406 megawatts on Thursday, topping Wednesday’s record of 81,351 megawatts.

ERCOT said it expects power usage on Friday to surpass those numbers, though the agency said it has enough resources to meet the demand.

The US heatwave mirrors similar searing conditions in Europe, which forced Greece to close one of its major tourist attractions, the Acropolis, on Friday.

Last week, the global average temperature was 63F (17.23C), which is the highest ever recorded.

Scientists say the temperatures are being driven by climate change and the naturally occurring weather pattern known as El Niño, which causes temperatures to rise and happens every three to seven years.

The world has already warmed by about 1.1C since the industrial era began and temperatures will keep rising unless governments around the world make steep cuts to emissions.