A heat wave is bringing scorching heat to New York and the I-95 corridor, with temperatures potentially reaching 100 degrees in Washington DC.

CNN
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A dangerous heatwave is bringing sweltering heat to much of the U.S., including the Ohio Valley and the Mid-Atlantic, this weekend. Meanwhile, a tropical storm could develop in the southwest Gulf of Mexico this weekend. Here’s the latest:

• Millions of Americans under heatstroke warning: Over the weekend, more than 100 million Americans are under extreme heat warnings, including those along the densely populated Interstate 95 corridor. A heat emergency has been issued in Washington, DC, where temperatures could reach the upper 90s or even triple digits for the first time since 2016.

• Tropical systems may develop: A new tropical storm could rapidly develop on Alberto’s heels this weekend. According to the National Hurricane Center, a moderate tropical storm could follow Alberto’s path into the southwestern Gulf of Mexico and northeastern Mexico this weekend. While this storm is not expected to reach the magnitude of Alberto, it could bring more rain to South Texas and cause new flooding concerns in the region and along the Gulf Coast.

• Heatwave returns to California: Heat warnings in California have been issued for parts of Southern and Central California, including Colusa County, as firefighters work to contain the 19,100-acre Sight Fire. High temperatures of 100 to 106 degrees are expected, which could hinder firefighting efforts. California has seen an increase in fire activity since the start of the year, according to the California Department of Forestry and Fire Protection. More than 89,700 acres have burned this year, compared with 5,747 acres burned during the same period last year.

• “Catastrophic flooding” in Iowa: Iowa Governor Kim Reynolds issued a disaster declaration for 21 northwest Iowa counties on Saturday, directing all available state resources to assist Rock Valley and other communities in responding to “catastrophic flooding.” In Rock Valley, all homes north of Highway 18 have been evacuated due to flooding. A level 2/4 excessive rainfall risk was in place for northern Iowa on Saturday, with radar showing an estimated 10 inches or more of rain expected in that part of the state. The heaviest rainfall is expected in the east. And in nearby Sioux Falls, South Dakota, nine people were rescued from rising waters caused by heavy rains in the past 24 hours, according to city emergency manager Regan Smith.

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• Flood threat in fire areas: Flood warnings have been issued for Ruidoso and other parts of New Mexico burned by the South Fork Fire after half an inch of rain fell in the morning and more was expected through the late afternoon. Rains from earlier this week caused mud and water to run off from burn scars, triggering flood emergencies and water rescues. Fire-scorched ground, also known as burn scar, loses its ability to absorb water effectively and becomes more susceptible to flooding.

• Search for “more deaths” in New Mexico fires: New Mexico officials reported that the wildfires have killed at least two people, destroyed 1,400 buildings, and displaced more than 8,000 residents. The mayor of hard-hit Ruidoso said he is preparing for more deaths from the fires and will bring in dogs to help search for “more fatalities.” The South Fork and Salt fires have burned an estimated 24,000 acres combined and remained 0% contained as of Friday. Evacuations remain in effect for residents of the Village of Ruidoso and the City of Ruidoso Downs, and additional evacuation orders have been issued for at least seven areas. Ruidoso residents will be allowed to return to their homes on Monday, but authorities are asking residents to bring at least a week’s worth of food and drinking water as grocery stores are not operating at full capacity. Meanwhile, FBI special agents are joining the investigation into the cause of the wildfires.

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Heatwave expected to intensify and spread this weekend

Further daily temperature records are expected through the weekend as the heat spreads to new areas and intensifies in others.

The combination of extreme heat and humidity will cause widespread heat index (feels like temperature) increases to 100 to 105 degrees Fahrenheit, possibly reaching 110 degrees Fahrenheit in the South Atlantic. Record low overnight temperatures will reduce your ability to cool down overnight, increasing health risks.

Temperatures in the capital could reach 100 degrees for the first time in eight years.

Washington, D.C., Mayor Muriel Bowser said a heat emergency will continue through the weekend and into next week, and the National Weather Service said temperatures could reach the upper 90s and even 100 degrees Fahrenheit in large parts of the city.

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Maryland Gov. Wes Moore signed a preparation proclamation Thursday in preparation for a potentially dangerous heat wave. Extreme heat watches are in effect for much of the region on Saturday, with dangerously hot temperatures expected to reach 105 to 110 degrees Fahrenheit, according to the National Weather Service.

The extended heat wave is a real concern. New York City residents could experience temperatures above 90 degrees Fahrenheit this weekend and into early next week, the longest such period on record for the city in June. For the first time this year, the National Weather Service has issued a heat watch for New York City.

Gov. Kathy Hockle on Tuesday announced the opening of a state emergency operations center that will monitor the situation in the state’s 62 counties and share resources with emergency managers. Earlier this week, New York City Mayor Eric Adams said he would open cooling centers across the city.

The city extended its heat stroke health warning until midnight Sunday, according to the Philadelphia Department of Public Health. Heat stroke warnings are in effect throughout the weekend in Philadelphia, where temperatures are expected to feel as high as 99 degrees.

A heat warning is in effect for New Jersey until 8 p.m. Sunday, according to the National Weather Service. Temperatures are expected to hover around 100 degrees Fahrenheit across the state on Saturday and Sunday.

In the West, the heatwaves are also back in full swing after a brief respite. Extreme heat warnings are already in effect for parts of California, Arizona and Utah. Over the weekend, temperatures are expected to reach 10 to 15 degrees above normal in Salt Lake City, Las Vegas, Sacramento and Bakersfield, California.