(NewsNation) — The deadly heat wave across the eastern half of the country has made for some scary situations.

Tens of millions in major cities across the northeast faced record high temperatures on Tuesday, the worst day of an oppressive heat wave that has spread since late last week.

According to the National Weather Service, temperatures in Washington and Boston soared to 101 degrees, beating previous records by as much as 6 degrees.

The extreme conditions claimed the life of a woman in Missouri, according to police. Shauna Thomas, 55, was found unresponsive in her sweltering apartment.

Police said Thomas’ power had been turned off on June 11 for non-payment, and she had no prior medical conditions.

In Philadelphia, the soaring temperatures have disrupted rail travel throughout the region, according to Nexstar affiliate WPHL. Both SEPTA and Amtrak have implemented speed restrictions and service adjustments to safeguard passengers and infrastructure.

High-speed intercity services — which typically run up to 150 mph — have been throttled to 80–100 mph, resulting in delays ranging from 15 minutes to over one hour.

Meanwhile, in New York and New Jersey, several attendees at outdoor high school graduation ceremonies were treated for heat exhaustion and related problems, including 16 taken to hospitals.

Two 16-year-old hikers were also rescued from a mountain in New Hampshire, overcome by the heat. Both were described as being in and out of consciousness while they were taken to a hospital.

The forecast for Wednesday across the Eastern United States called for extended hot conditions before temperatures begin to cool down and provide a respite.