Strong thunderstorms will develop around midday Thursday, July 27, and track east during the afternoon and evening, the National Weather Service said.
Some storms could be severe with downpours, large hail, and damaging winds. A brief tornado is also possible, the weather service said in a Hazardous Weather Outlook statement issued early Thursday morning.
Areas in orange in the first image above from AccuWeather.com have the highest chance of seeing severe storms on Thursday.
With temperatures reaching the low to mid-90s amid high humidity, heat indices on Thursday will be 100 degrees or more.
"While every summer has heat, the next several days will be dangerously hot," the National Weather Service said. "Heat is one of the most deadly weather hazards -- don't underestimate it."
Friday, July 28 could be the warmest day of the week -- and the year -- as the high temperature approaches the 100-degree mark in much of the area, with partly sunny skies.
"There is a chance that the heat index (the combination of the temperature and humidity) may reach 105 on Friday," the National Weather Service said in a statement.
In some parts of the Northeast, the heat index could hit as high as 110 degrees. (Click on the second image above.)
It will be partly sunny on Saturday, July 29 with a high temperature of around 90 degrees.
Scattered afternoon and evening showers and storms will arrive Saturday as a cold front pushes through that will bring a halt to the heat wave.
Sunday, July 30 will be pleasant and comfortable with mostly sunny skies and a high temperature of around 80 degrees.
The high temperature is expected to remain around 80 degrees for the following few days with less humidity.
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