About 150 million Americans — or around 45% of the US population — are under heat alerts that include more than 30 states extending from California to Maine, according to the National Weather Service. The heat will peak today and Friday across the eastern half of the country.
The Northeast will easily see their warmest temperatures of the year, as highs in Washington, Philadelphia and New York City approach 100 degrees and the heat index could reach a dangerous 105 degrees today and tomorrow.
In the Southwest, the extreme heat is slowly waning. Phoenix’s night time low temperature finally dropped below 90 degrees for the first time in 16 days and the record breaking streak of 110 degrees or above high temperatures could end on Sunday.
6 min ago
Philadelphia's under a heat health emergency through Saturday and opening cooling centers
From CNN's Michelle Watson
Philadelphia's health department declared a "Heat Health Emergency" for Thursday through Saturday, the agency said in a news release.
"During very hot weather, the City will declare a Heat Health Emergency. When we declare a Heat Health Emergency, we activate several City services to ensure our residents stay safe," the department said.
The city is increasing its outreach to those experiencing homelessness in the area to help them find relief from the heat the release said.
The city's designated more than a dozen free libraries as cooling centers that are open to the public, from 10 a.m. to 7 p.m. local time each day Thursday through Saturday. Nearly 20 parks and recreation centers will also be open as cooling centers from 11 a.m. to 7 p.m. each day.
According to the National Weather Service (NWS), the Philadelphia is currently under an excessive heat warning.
"Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities," NWS said.
6 min ago
These are the signs to watch for to stay safe in extreme heat
From CNN's Christina Maxouris
Miami-Dade County Homeless Trust representatives distribute bottles of water and shelter information during a heat wave in Miami, Florida, on July 25. Eva Marie Uzcategui/Bloomberg/Getty Images
Heat is called a “silent killer” because you can’t see it but it can quickly turn deadly. The very young, the elderly and those who have to spend long periods of time outside, such as outdoor workers and people experiencing homelessness, are particularly vulnerable.
What happens to your body in extreme heat: The body is used to a range of temperatures between 97 and 99 degrees Fahrenheit (36 to 37 degrees Celsius). When it rises above this, the body sweats to cool down but the higher the temperature, the harder it is to cool down — especially if it’s humid, which means sweat can’t evaporate as easily.
The second way your body cools itself down is by dilating blood vessels and upping your heart rate, which helps bring heat and blood to the surface of your body and release that excess heat.
What to watch for: Heat exhaustion can occur when your body overheats. This can bring dizziness, nausea and headaches. Heat stroke is more serious and happens when the body’s temperature climbs to 104 degrees Fahrenheit (40 degrees Celsius) or higher. Untreated, it can damage organs or even cause death.
One of the main recommendations for people to protect themselves from the heat is to stay inside and avoid exercise during the hottest parts of the day, especially between 11 a.m. and 3 p.m. When outside, stay in the shade.
Experts advise that people wear light, loose-fitting clothes, a hat and sunscreen and drink plenty of water, even if you don’t feel thirsty, but avoid alcohol and caffeinated drinks.
According to Judith Linden, a professor in the emergency medicine department at Boston University’s school of medicine, it's also important to watch out for others.
“If somebody starts feeling light-headed, dizzy, nausea or headache, that is the time to act immediately. That means getting them out of the heat and into a cool environment,” she told CNN.
More than 150 million people across more than 30 US states are under heat alerts Thursday — about 45% of the US population.
The dangerous conditions continue in the Southwest in places like Phoenix, which have seen temperatures well in the triple digits for weeks.
Parts of the Northeast expected to sizzle under their highest temperatures this year.
Scientists say the record-breaking heat in parts of Europe and the US this month could have been “virtually impossible” without climate change.
About 150 million Americans — or around 45% of the US population — are under heat alerts that include more than 30 states extending from California to Maine, according to the National Weather Service. The heat will peak today and Friday across the eastern half of the country.
The Northeast will easily see their warmest temperatures of the year, as highs in Washington, Philadelphia and New York City approach 100 degrees and the heat index could reach a dangerous 105 degrees today and tomorrow.
In the Southwest, the extreme heat is slowly waning. Phoenix’s night time low temperature finally dropped below 90 degrees for the first time in 16 days and the record breaking streak of 110 degrees or above high temperatures could end on Sunday.
Philadelphia's health department declared a "Heat Health Emergency" for Thursday through Saturday, the agency said in a news release.
"During very hot weather, the City will declare a Heat Health Emergency. When we declare a Heat Health Emergency, we activate several City services to ensure our residents stay safe," the department said.
The city is increasing its outreach to those experiencing homelessness in the area to help them find relief from the heat the release said.
The city's designated more than a dozen free libraries as cooling centers that are open to the public, from 10 a.m. to 7 p.m. local time each day Thursday through Saturday. Nearly 20 parks and recreation centers will also be open as cooling centers from 11 a.m. to 7 p.m. each day.
According to the National Weather Service (NWS), the Philadelphia is currently under an excessive heat warning.
"Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities," NWS said.
Miami-Dade County Homeless Trust representatives distribute bottles of water and shelter information during a heat wave in Miami, Florida, on July 25. Eva Marie Uzcategui/Bloomberg/Getty Images
Heat is called a “silent killer” because you can’t see it but it can quickly turn deadly. The very young, the elderly and those who have to spend long periods of time outside, such as outdoor workers and people experiencing homelessness, are particularly vulnerable.
What happens to your body in extreme heat: The body is used to a range of temperatures between 97 and 99 degrees Fahrenheit (36 to 37 degrees Celsius). When it rises above this, the body sweats to cool down but the higher the temperature, the harder it is to cool down — especially if it’s humid, which means sweat can’t evaporate as easily.
The second way your body cools itself down is by dilating blood vessels and upping your heart rate, which helps bring heat and blood to the surface of your body and release that excess heat.
What to watch for: Heat exhaustion can occur when your body overheats. This can bring dizziness, nausea and headaches. Heat stroke is more serious and happens when the body’s temperature climbs to 104 degrees Fahrenheit (40 degrees Celsius) or higher. Untreated, it can damage organs or even cause death.
One of the main recommendations for people to protect themselves from the heat is to stay inside and avoid exercise during the hottest parts of the day, especially between 11 a.m. and 3 p.m. When outside, stay in the shade.
Experts advise that people wear light, loose-fitting clothes, a hat and sunscreen and drink plenty of water, even if you don’t feel thirsty, but avoid alcohol and caffeinated drinks.
According to Judith Linden, a professor in the emergency medicine department at Boston University’s school of medicine, it's also important to watch out for others.
“If somebody starts feeling light-headed, dizzy, nausea or headache, that is the time to act immediately. That means getting them out of the heat and into a cool environment,” she told CNN.
