Summer has officially started and temperatures across the Northeast are expected to approach triple digits.
The National Weather Services has forecast potentially record-breaking hot temperatures as the season begins on Wednesday.
Readings are expected to be in the mid- to high-90s Wednesday and Thursday in cities including Philadelphia, New York and Boston.
But humidity could make it feel even hotter.
Health officials have warned residents to drink water, stay out of the sun and in air conditioning, and to check on elderly neighbors and pets.
"Cooling centers" have been set up in public buildings in dozens of cities throughout the region for people without air conditioning.