First day of summer brings potentially dangerous Northeast heat wave

Days like this make Nelson Sensenig really appreciate getting into the ice business.

"Where we bag the ice is about 40 degrees and the freezer is 20," said Sensenig, president of White Oak Ice Company in New Holland, Pa.

No doubt a good place to escape what could be record-breaking high temperatures in the northeastern United States this first day of summer.

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Heat watches and warnings have been issued for several states. Temperatures in places like Boston, New York City, Washington, D.C., and Philadelphia will soar to the mid- to upper 90s on Wednesday and Thursday. High humidity could make it feel like 100 to 105. Fans and air conditioners are in demand at stores from Chicago to Connecticut.

Fifteen to 20 degrees above normal could spell trouble for children, the elderly or people working outdoors.

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"If you are in an area affected by the extreme heat, understand the warnings signs of heat-related illnesses," forecasters cautioned in an alert.

Sensenig's customers in northeastern Pennsylvania are getting the worst of it. They are under an excessive heat warning until Friday. Many cities are reportedly opening cooling centers and spray stations to help people escape the swelter.

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"The combination of the heat and humidity will result in dangerous conditions during the afternoon and early evening hours," the National Weather Service said. "The urban centers such as center city Philadelphia will tend to hold the heat through the night that built up during the day."

Business is expected to double at White Oak Ice Company, where Sensenig estimates they will sell 30,000 bags of ice on Wednesday.

"The phone has been going," he told Yahoo. "People double up on days like this."

Forecasters said the Northeast will gradually start to cool off by late Friday and Saturday. But heat advisories could return by Sunday, when states in the Southwest are expected to get the summer's first wave of triple-digit temperatures.