A massive heat dome will continue to bring record heat to large swaths of the country on Wednesday, including sweltering temperatures across the Eastern U.S. that has prompted early dismissals in some schools.
Fifty-one million people are under heat advisories and heat warnings Wednesday from eastern Missouri to Long Island, New York, as the dome's high pressure brings hot and humid air from the south up north.
High temperatures today will stretch from St. Louis, Missouri, and Memphis, Tennessee, eastward up and down the coast from Raleigh, North Carolina, up to New York City and Washington, D.C.
Temperatures are forecast to be 10 to 15 degrees higher today, likely leading to spotty record highs.
New York City is forecast to hit a high of 91 degrees Fahrenheit on Wednesday, with a max heat index of 98, and Washington D.C. a blazing 100 with a max heat index of 104.
It comes after much of the Midwest baked under scorching temperatures Tuesday that were also 10 to 15 degrees higher than normal for this time of year. Chicago hit 99 degrees and Indianapolis 94 on Tuesday — marking the hottest day of the year for both cities.
In Philadelphia, dozens of schools that lack adequate air conditioning had early dismissals on Tuesday that will continue Wednesday to avoid keeping kids in hot classrooms.
In New York City, the U.S. Open is preparing to give players additional breaks as they play in the heat.
In Washington, D.C., a heat emergency has been declared starting at noon ET. And a Code Orange air quality alert has been issued over air quality concerns.
The heatwave won’t last long as cooler air from Canada will head southward across the Great Lakes and New England region into the Mid-Atlantic by Thursday.
The cold front mixing with hot air will trigger lines of thunderstorms. The highest threat for severe weather will be later Wednesday into the evening from Indiana eastward across the northern Mid-Atlantic, the National Weather Service’s early morning advisory said. That will affect cities like Baltimore, Pittsburgh and Philadelphia. Some more strong storms could also form Thursday further south.
With the cold front, temperature highs Thursday will be 10 to 20 degrees cooler with cooler humidity.
