Washington, Jul 18 (IANS): More than 90 million people in the US, nearly one-third of the population, are under heat alerts as a blistering heat wave continues to sweep the country.

In its latest update, the National Weather Service (NWS) said that high temperatures are set to impact residents in the West and the South of the country, with multiple cities expected to break heat records in the coming weekend, reports Xinhua news agency.

Of the 90 million people, at least 50 million have been under heat alerts for the past 10 days.

Heat advisories, excessive heat warnings and excessive heat watches are currently in place in California, Nevada, Arizona, New Mexico, Louisiana, Texas, Arkansas, Mississippi, Alabama, Oklahoma and Florida.

Temperatures in some desert areas soared past 48 degrees Celsius during the day on Monday and remained more than 32 degrees overnight.

The temperature in California's Death Valley hit as high as 53.3 degrees on Sunday, according to NWS.

Also on Sunday, Las Vegas shattered its record with 46.6 degrees.

Meanwhile in Phoenix, temperatures on Monday once again hit 43.3 degrees for a record-tying 18th consecutive day, reports CNN.

The record is expected to be broken on Tuesday as the heat wave continues unabated, with temperatures of at least 46.1 degrees in the forecast for the Arizona state capital every day through the coming weekend.

As the scorching temperatures persist, there have been 12 confirmed heat related deaths recorded in Phoenix just for the first week of July, and 55 heat related deaths overall so far this year, according to data from the Maricopa County Department of Public Health

More than 1,500 record-high temperatures were recorded in the US so far this month, according to the National Oceanic and Atmospheric Administration.

The heat wave is one part of the extreme weather conditions hitting the US as heavy thunderstorms, tropical storms and wildfire smoke also impact some areas of the country.