More than 185 million people across from South Dakota to Florida and up the East Coast to Boston are on alert for widespread, dangerous heat on Monday and into the new work week, and parts of the Southeast could experience the brunt of the sweltering conditions.

       On average, nearly 2,000 Americans die from extreme heat each year, according to CDC data going back to 2020.

       The highest temperatures on Monday will be focused in the southeast from the Carolinas to Florida where extreme where heat indices -- that is, what the temperatures feel like when humidity is factored in -- are forecast to be between 105 and 113 degrees.

       Parts of Mississippi and Louisiana are on alert for heat indices up to 120 degrees.

       Extreme heat is also expected to continue on Monday and Tuesday in the Midwest, where over the weekend temperatures felt between 97 to 111 degrees from Lincoln, Nebraska, up into Minneapolis.

       The Northeast coast from Philadelphia to Boston, including New York City, are in store for multiple days of dangerous heat. Heat indices in the Northeast are forecast to make it feel like the mid-90s to 113 on Monday.

       In addition to the sweltering conditions, smoke from Canadian wildfires is expected to continue to create hazy conditions in New York City, New Jersey and Connecticut. Over the weekend, smoke from multiple wildfires in Canada prompted an air-quality alert.

       Looking ahead to the work week, potentially life-threatening heat and humidity are expected to continue across the eastern half of the country through Wednesday. Major cities including St. Louis, Memphis, Charlotte, Savannah, Tampa and Jackson, Mississippi, are all likely all see actual temperatures in the upper 90s to low 100s.

       A prolonged heat wave is forecast for those regions as an abundance of tropical moisture settling in is expected to drive the feels-like temperatures up to between 105 to 115 degrees over multiple consecutive days.

       Nighttime and early mornings are not expected to provide relief from the sweltering conditions. Overnight and early morning lows are expected to fall only to the 70s or higher.

       Between Monday and Wednesday, large portions of the Southeast are expected to be under an extreme heat risk at a four-out-of-four level, including the cities of Atlanta, Charlotte, and Jacksonville and Tallahassee, Florida.

       On Sunday, Tampa, Florida, broke an all-time heat record -- reaching 100 degrees for the first time in 130 years of record-keeping.

       ABC News' Youri Benadjaoud contributed to this report.