In Paterson, New Jersey, over 100 individuals required medical attention during two outdoor graduation ceremonies on Monday, as the heat index soared to 107 degrees. That evening, Mayor Andre Seig declared a state of emergency, leading to the cancellation of all recreational activities due to the extreme heat.

Monday saw record high temperatures exceeding 60 degrees nationwide, with predictions extending from the southeast up to New England throughout the week.

Preliminary daily records were established on Tuesday in New York City (99 degrees), Philadelphia (for the first time since 2012), and Raleigh, North Carolina (100 degrees).

New monthly records for June were set in Boston (101 degrees) and Providence, Rhode Island (100 degrees), while Newark recorded a staggering June high of 103 degrees.

The National Weather Service indicates that the oppressive heat conditions are likely to persist through the evening.

“Overnight lows are anticipated to remain in the ’70s, with urban areas along the East Coast struggling to dip below 80 degrees at night,” the Weather Service remarked in a brief forecast on Tuesday..

These elevated temperatures are attributed to high-pressure ridges, which are currently parked over the eastern United States. Known as thermal domes, these systems effectively trap heat in the region, leading to prolonged periods of elevated temperatures.

While some relief may arrive towards the weekend, heat and humidity levels are expected to remain elevated over the coming days.

“The most severe cumulative heat impacts are expected on Friday across the eastern Ohio valleys stretching from the Mid-Atlantic to Thursday, resulting in multi-day oppressive heat,” stated the Weather Service.

All individuals are at risk for heat-related illnesses and fatalities, but the excessive heat and humidity—especially over several days—pose a particular risk to children, those with pre-existing health conditions, the elderly, and outdoor workers. These health concerns are increasingly pressing as climate change leads to more frequent, intense, and lasting heat events.

While the eastern U.S. battles the heat dome, a severe storm system could impact parts of Wyoming, Colorado, South Dakota, and Nebraska. Additionally, heavy rainfall and flooding are likely for much of New Mexico and southwestern Texas.