Extreme heat to scorch central, southern US on Father’s Day

The year’s most significant heat wave so far is expected to roast a large portion of the central and southern United States on Father’s Day Sunday with potentially record-breaking high temperatures, four days away from summer’s official start.

The National Weather Service warned people in the South and Midwest planning to celebrate dads outdoors on Sunday to stay cool amid a major heat risk, with high temperatures into the 90s in some areas.

The intense heat wave won’t stop there. An expansive and exceptionally strong heat dome will build Sunday over the East and stretch into the Midwest and Great Lakes over the next few days, with the heat expected to persist through the week.

Heat domes trap air in place and bake it with abundant sunshine for days on end, making each day hotter than the last.

The final Sunday of spring will be a scorcher in the Plains and Midwest, where temperatures will reach the mid- to upper 90s, according to the Weather Prediction Center.

People living across the Great Lakes region can expect temperatures in the upper 80s and low 90s.

The Mississippi River Valley will be slammed with the worst of Sunday’s sweltering conditions, with large portions of both states facing a Level 3 – or major – risk of heat-related impacts.

The National Weather Service office in St. Louis encouraged residents to take extra precautions Sunday for its hottest day of the year. “It will feel like 100-105 during the afternoon hours. We aren’t used to this kind of heat yet,” forecasters wrote on X, formerly Twitter.

Sunday’s unrelenting heat will be felt across states including Kansas, Illinois, Tennessee, Arkansas and Mississippi, according to the weather service.

Some smaller pockets of Level 4 – or extreme – heat will be felt in a few locations such as Atlanta, where Sunday afternoon temperatures could reach 94 degrees by the afternoon.

Millions will face heat-related health risks as conditions reach extreme levels into this week, according to a scale from the National Weather Service and the Centers for Disease Control and Prevention. Heat is the deadliest form of weather in the US, killing more than twice as many people each year on average as hurricanes and tornadoes combined.

Persistent heat could break records this week

The extreme temperatures and uncomfortable heat will seep into the larger cities of the Midwest and Northeast by the start of the workweek. On Monday, Chicago temperatures could hit 94 degrees with the heat index at 97 degrees, according to forecasters at Chicago’s weather service office.

The high temperatures for the Upper Ohio Valley and Great Lakes regions will soar into the mid- and upper 90s on Monday, with the possibility of tying or breaking numerous records, according to the Weather Prediction Center.

The potential for record-shattering heat will last across the Ohio Valley and the Northeast through Friday, with some areas hitting heat indices of 105 degrees, the Weather Prediction Center said.

A Level 3 heat risk is expected to affect large portions of states including Wisconsin, Illinois, Indiana and Ohio on Monday, according to the weather service. Meanwhile, much of the southern half of Iowa faces an extreme heat risk on Monday.

Weather service forecasters in Des Moines, Iowa, warned of high heat and humidity through Tuesday as temperatures push into the 90s and heat index values hit near-triple digits.

“Morning lows will be just as impressive, as temperatures remain in the mid- to even upper 70s,” the Weather Prediction Center said.

“The combination of heat, humidity and little overnight relief will bring potentially widespread, significant heat-related impacts to anyone without adequate hydration or reliable cooling,” according to the center.

In Detroit, where daytime temperatures are expected to hit the high 90s, the city’s urban core won’t see much relief after dark, where weather service forecasters say overnight lows will only dip to the 70s this week.

The sweltering conditions will continue to shift into the eastern and northeastern US by Tuesday.

CNN’s Elisa Raffa contributed to this report.

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