- A heat wave is forecast to hit the East Coast and Midwest and last through at least Friday.
- More than 76 million people were under some level of heat alert as of this morning. About 150 million people are expected to experience temperatures above 90 degrees Fahrenheit.
- Heat warnings, watches or advisories were in effect from Iowa to Maine, affecting Detroit, Cleveland, Cincinnati, Pittsburgh, Philadelphia, Boston, New York and other cities.
- More than 100 record highs are possible today through Saturday, where temperatures soaring 10-25 degrees above average will lead to highs in the 90s to close to 100 degrees in the Midwest, mid-Atlantic and Northeast.
New Mexico governor declares state of emergency amid wildfires
New Mexico Gov. Michelle Lujan Grisham has declared a state of the emergency as wildfires threaten communities in the southern part of the state.
The South Fork fire, which forced the evacuation of nearly 7,800 people Monday night from the village of Ruidoso, more than doubled in size to nearly 14,000 acres in less than 24 hours.
It is 0% contained, according to the New Mexico State Forestry Division.
"This is a full suppression fire, and all available resources are responding to help secure line and perform point protection for homes in and around Ruidoso," fire officials said in a Tuesday afternoon update.
A neighboring fire southwest of Ruidoso has scorched nearly 5,000 acres in the Mescalero Apache Reservation and is also 0% contained.
The Tribal Council declared a state of emergency for the reservation.
Air quality alerts in some areas with high heat
Air quality alerts are in effect for parts of six states: Connecticut, Massachusetts, New Hampshire, New Jersey, New York and Ohio.
Additional alerts are expected to go into effect on Wednesday for areas in Indiana, Maine and Michigan.
When heat reacts with air pollution, it accelerates the formation of ground-level ozone, which can cause coughing, shortness of breath and lung irritation. When ground-level ozone levels are high, the CDC advises people to spend more time indoors and avoid strenuous activities outside.
Dehydration risk can mount as hot days persist
Reporting from Chicago
In Chicago, where the 97-degree weather broke records on Monday, the heat wave is just getting started, with another seven days of high temperatures and humidity expected.
At one of the city's public beaches, Jason Lach with the Chicago Fire Department warned about lack of hydration even while people sought to cool off in the lake.
“You don’t realize you’re sweating and dehydrating as much as you are — even spending 20, 30 minutes in 63-degree water like we have right now, you can get dehydrated and tired quickly and become over exerted,” Lach warned.
Dr. George Chiampas, attending physician of emergency medicine and sports medicine at Northwestern Medicine, advised that a sports drink with electrolytes and sugar may be better to replenish lost fluids than just water. For people who exercise or work outdoors, it’s critical to stay at a “balanced hydration level,” Chiampas said.
By the fourth or fifth day of high temperatures, the body can begin to lose weight from lost fluids and become even more vulnerable to the heat. Chiampas' guidance: “Check your weight in the morning, and the next and then at night. If you’re down three or four pounds, drink to get back to your baseline body weight.”
A key sign of serious dehydration is the color of urine, Chiampas added: It "should never be dark like iced tea,” he said — a well-hydrated state is indicated by a pale, “light lemonade color.”
911 system was temporarily down across Massachusetts but has been restored
Amid the severe heat forecasts, 911 systems across Massachusetts went down for almost 2 hours on Tuesday, preventing emergency calls from going through statewide.
Service was restored at 3:49 p.m.
During the outage, members of the public were advised to call direct lines of local district police stations and use call boxes to reach fire departments or to report other medical emergencies.
Boston Mayor Michelle Wu addressed the issue during a news conference meant to focus on the Boston Celtics' NBA Championship win.
It’s not yet clear what caused the outage. State officials said they continue to investigate what led to the disruption.
Leaving pets or children inside hot cars can lead to tragedy. When it’s 80 degrees outside, a car can reach 109 degrees in 20 minutes and 123 degrees in an hour, according to the CDC.
Consumer Reports explains the dangers and shares tips on how to prevent a death from happening, no matter the weather.
Heat wave will hammer states with low air conditioning access
The heat wave coming for the Northeast will hit harder in states where air conditioning is less common.
Most of New Hampshire, Maine and Vermont are under heat advisories or excessive heat warnings. The forecast in Manchester, New Hampshire, calls for temperatures of 99 degrees F tomorrow. But each of these states lags behind the U.S. average for air conditioning coverage, according data collected in 2020 by the U.S. Energy Information Administration.
About 89% of U.S. households had some kind of air conditioning and most — about two-thirds — featured central air as of 2020. But only 67% of households in Vermont had A.C. In Maine, that figure was 70%. New Hampshire came in at 78%.
The figures took stock of which households had room air conditioners and which had central air. Fewer than one in 10 households in Maine and Vermont had central air. Around 21% had it in New Hampshire.
Google searches for “air conditioning” and related terms were spiking in Vermont, New Hampshire and Maine, according to the search engines’ trend-tracking tool.
The National Weather Service’s heat-risk rating tool suggests parts of these states will experience “major” or “extreme” heat risk during the next three days. “Extreme” risk means forecasters expect long-duration heat with little overnight relief, which is expected to impact health systems and infrastructure.
High temperatures are increasingly concerning to economists
Workers across the U.S. are enduring scorching temperatures this week, a factor that has become top of mind for many economists who say that climate change could become a long-term drag on production in addition to a serious health risk.
Economists at the Federal Reserve Bank of San Francisco wrote in a recent letter that the construction industry faces particular risks.
“Extreme heat is most likely to affect economic outcomes through the construction sector for two reasons,” the economists wrote. “First, construction makes up a larger share of economic output than other vulnerable sectors, like agriculture. Second, decreases in construction productivity slow capital accumulation and therefore have long-lasting effects on macroeconomic outcomes.”
Beyond the economic downsides, heat waves are expected to become an increasingly serious risk to the health of many laborers. The Adrienne Arsht-Rockefeller Foundation Resilience Center found that injuries due to severe heat total about 120,000 every year and are expected to hit about 450,000 annually by 2050. High temperatures can cause workers to slow down and be clouded with fatigue, which can lead to mistakes, injuries and in extreme cases death.
The Occupational Safety and Health Administration, the federal agency tasked with overseeing worker safety, has guidelines about how much physical work can be done safely outside in hot conditions. In construction, heat stress becomes a concern at a wet bulb temperature of 77 degrees F, and is not safe when above 91 degrees. A wet bulb reading measures heat risk in sunlight, factoring in temperature, humidity, wind speed and solar radiation.
Labor, environment and health care advocates have signed a petition requesting that FEMA consider extreme heat a major disaster. NBC News’ Maura Barrett reports on the increasing number of deaths related to heat in the U.S. over the last 30 years.
South Texas expects flooding and extreme rain as cyclone nears
As much of the country suffers under extraordinary heat, southeast Texas could soon deal with a deluge.
Potential Tropical Cyclone One, a large storm lurking in the Gulf of Mexico, is expected to make landfall on Mexican shores Wednesday night. Heavy rainfall will likely precede it as soon as Tuesday evening. The storm is expected to have winds of about 40 mph.
Although the storm is not expected to directly hit Texas, the National Hurricane Center said it’s so massive that it could have severe effects there.
“Moderate coastal flooding is likely along much of the Texas Coast beginning today and continuing through midweek,” forecasters wrote. “We expect this system to have a large area of heavy rains, moderate coastal flooding and tropical-storm-force winds well north of the center."
Corpus Christi and San Antonio are among the Texas cities with a 40% or greater chance of flash flooding, according to the forecast.
Symptoms and risk factors for heat-related illness
In extreme heat, the first symptoms of exposure can happen in as little as 15 minutes. Signs of heat exhaustion can start with a headache, nausea, muscle spasms, dizziness or shortness of breath. When it’s above 90 degrees, people of all ages need to be careful, not just those who are older or very young.
Certain medications can also make people more vulnerable to heat's effects. Some drugs for blood pressure can aggravate dehydration, while beta blockers that slow the heart rate can make it more difficult to detect warning signs.
Many drugs taken for mental health disorders, including antipsychotics and antidepressants, can affect the body’s thermostat and increase the risk of a heatstroke. Scientists think this is because of the medications’ effects on the hypothalamus, the part of the brain that regulates our body’s temperature. Antidepressants in particular can interfere with internal temperature control and prevent sweating, which is critical for the body to cool itself.
Stimulants for ADHD can also raise body temperature.
Doses of some drugs may need to be adjusted temporarily to avoid deadly side effects during heat waves, according to the Centers for Disease Control and Prevention.
Firefighters gain advantage over Los Angeles County fire
A wildfire along the busy Interstate 5 corridor in northern Los Angeles County is 24% contained after growing by more than 1,000 acres overnight.
The Post Fire, which had previously prompted the evacuation of some 1,200 campers and recreationists near Gorman, California, has scorched more than 15,600 acres since erupting Saturday.
A red flag warning indicating high-risk fire conditions remains in effect until Tuesday evening because of low humidity and strong winds.
In a briefing Monday, Daniel Swain, a UCLA climate scientist, warned that the upcoming fire season could be especially active after two years of heavy rain and snow. Vegetation fed by the heavy precipitation will begin to dry out during the hot summer months — a process called fuel loading that could trigger more fires later in the season.
“The good news is increasingly in the rear-view mirror,” Swain said. “The bad news is that I think that the back half of this season is going to be much more active, with a lot more concerning level of wildfire activity in a lot of areas, than the first half.”
Across California, firefighters are battling some 2,103 wildfires in total, which have burned more than 66,000 acres, according to the California Department of Forestry and Fire Protection. At least 22 structures have been damaged or destroyed. No fire deaths have been reported yet this season.
Schools forced to change schedules due to high temperatures
With the heat index reaching over 100 F in some areas, public schools in New York and Massachusetts have changed their schedules like they would for a snow day.
In Worcester, Massachusetts, one of the largest public school districts in the state, summer break will start a few days early.
"Because of the age of our buildings, many do not have air conditioning. We regret that we are ending the school year in an abrupt manner, but we want to ensure our students and staff are safe in what are predicted to be unusually hot temperatures," Rachel H. Monárrez, the superintendent of Worcester Public Schools, wrote in a letter to families and staff.
When it's hot out, students learn less in classes without AC, according to a study from Harvard University's Kennedy School of Government. Each degree higher than the school year's average temperature showed a 1% decline in learning for the entire year when a school did not have AC, the study found.
Schools in multiple New York districts, including Buffalo, Rochester and Syracuse, will let students in pre-K through 8th grade leave after lunch.
What is a heat dome?
This week’s extreme heat is caused by a “heat dome” parked over much of the Midwest and Northeast. A heat dome is a high-pressure system in the upper atmosphere that traps warm air in place, similar to how a lid traps heat over a pot of boiling water.
Heat domes can build and intensify over a region by blocking cooler winds or preventing clouds from forming, thus fueling persistent high heat and humidity.
Scientists say that climate change is increasing the likelihood of heat domes, making extreme heat events both more frequent and more intense in a warming world.
Some cities will feel the heat more due to high humidity
In Chicago, Pittsburgh and Washington, D.C., the heat index value — a measure of the temperature the body feels with humidity factored in — is likely to exceed 100 degrees. Humidity levels in those cities are expected to range from around 60% to 73%.
For people in New York and Boston, meanwhile, temperatures could feel like they're in the high 90s, given forecast humidity levels around 63%.
The heat index is a crucial measure of extreme heat, since the sweat our bodies make to cool us evaporates less quickly in high humidity, making us feel hotter.
Chart: Heat deaths over the last 30 years
According to data from the Centers for Disease Control and Prevention, 1,168 people died of heat in 2023 — the highest toll in 30 years. That figure does not include deaths in which heat was a factor but not the cause, which would make the total much higher.
A different kind of extreme in Oregon
While much of the Midwest and the East Coast will be sweltering under a heat dome, other areas of the country are bundling up.
Parts of southern Oregon and Northern California faced a freeze warning early this morning.
Yesterday, Kirk, Oregon, had a low temperature of 19 F, making it the coldest place in the U.S. Today, forecasters are calling for a low of 38 in Kirk.
In Texas, by contrast, the country's highest temperature of the day was recorded at 114 degrees in Rio Grande Village. The area remains under extreme heat risk today.
Stubborn, record-breaking heat dome to last for days
Reporting from Pittsburgh
Tens of thousands of people in the Pittsburgh area lost power last night because of storm damage, a particular concern because the city reached 100 F for the first time in 30 years.
Some 35,000 people in Pennsylvania were still without power this morning, according to PowerOutage.us.
The residents were among the 76 million people under heat alerts today, with temperatures in some places expected to be than 25 degrees above average. About 100 daily records are likely to be shattered this week.
The heat dome causing these extremes is set to move south around the weekend, providing some relief to the Northeast, but cities including Washington, D.C., could still experience up to eight days of severe heat.
The news comes as several health care and labor groups filed a petition to get FEMA to recognize extreme heat as a major disaster.
New York state set to swelter in triple digit heat
Parts of New York state will reach beyond 100 degrees today, the weather service has warned.
In Rochester, on the shores of Lake Ontario, it will reach 102 by 3 p.m., with a heat index — a measure of how hot it feels that factors in humidity — of 104.
The weather service urged people to find air-conditioned spaces, avoid strenuous work outside and to check on family members and neighbors.
National Weather Service warns of dangerous and unusual heat in Great Lakes and Northeast
The National Weather Service said early today that this week's heat wave could bring record temperatures and relatively unusual danger to northern parts of the country.
Temperatures are set to hit the upper-90s and possibly reach the 100 mark today and tomorrow, it said, including into northern New England.
Already today, temperatures are in the mid-70s, which in many areas either ties or breaks morning low records.
"The early arrival of this magnitude of heat, the duration, abundant sunshine, and lack of relief overnight will increase the danger of this heatwave beyond what the exact temperature values would suggest," the service said.
"This is especially true for those without adequate air conditioning, which becomes more of a concern for locations father north that are not a accustomed to periods of persistent, intense heat."
Hottest place in the U.S. climbed to 114 F yesterday
As the heat turns up across much of the country, Texas boasted the highest temperature yesterday.
Rio Grande Village reached 114 degrees Fahrenheit, making it the hottest place in the U.S., according to the National Weather Service.
National forecasters are calling for a high of 113 degrees F there today and have designated it a Category 4 — extreme — risk for heat-related impacts. At that level of “long-duration extreme heat with little to no overnight relief,” anyone without effective cooling or adequate hydration is affected, the agency warned.
Heat wave will be ‘dangerous and long,’ National Weather Service predicts
Light winds and persistent heat over multiple days could make this week’s wave especially dangerous, the National Weather Service's Weather Prediction Center said yesterday afternoon.
Daily temperatures in the Midwest and the Northwest could reach record highs. The center expects the heat index — what the temperature feels like to the human body — to peak from 100 to 105 degrees Fahrenheit in many locations.
By the weekend, the most intense heat is expected to shift toward the Northeast urban corridor and the mid-Atlantic — areas that include Boston, New York, Philadelphia, Baltimore and Washington.
The National Weather Service advises people who don’t have access to reliable air conditioning to find ways to cool down, which may include staying in the shade, drinking lots of water and wearing loose, light-colored clothing. People and pets should never be left alone in closed cars to avoid overheating.
California firefighters gain ground against big wildfires after hot and windy weekend
Firefighters increased their containment of a large wildfire in mountains north of Los Angeles yesterday after a weekend of explosive, wind-driven growth along Interstate 5.
The Post Fire was 8% surrounded after having scorched nearly 23 square miles and forced the evacuations of at least 1,200 campers, off-roaders and hikers from the Hungry Valley recreation area Saturday.
“That 8% is good because it means we are increasing and bolstering our containment lines,” said Kenichi Haskett, a Los Angeles County Fire Department section chief.
Firefighters hope to hold the fire at its current size, but further growth is possible, Haskett said.
The fire broke out as weather turned hot and windy in a region where grasses spawned by a rainy winter have long since dried out and burn easily.
How does heat kill?
Heat kills more people in the U.S. every year than any other type of weather event. More than 1,100 people died from extreme heat last year, according to provisional data from the Centers for Disease Control and Prevention. The figure doesn't include deaths in which heat was a contributing factor rather than an underlying cause — which would more than double the figure.
The number of heat-related deaths has increased steadily in the U.S. in the last few years. Multiple factors may be responsible: Climate change makes heat waves longer, more frequent and more intense. But rising rates of homelessness and a lack of access to air conditioning in the U.S. have also exposed more people to extreme temperatures.
Severe heat can cause a variety of illnesses, from skin rashes and muscle cramps on the milder end to more worrisome symptoms such as fainting, dizziness, headache or nausea. The most serious heat-related illness — heatstroke — occurs when the body can’t regulate its own temperature. People suffering heatstroke may die if they’re not treated right away.
In other cases, extreme heat may aggravate underlying health problems such as heart disease or high blood pressure. As people’s body temperatures rise, their heart starts to pump faster to increase blood flow to the skin, which can place added strain on the cardiovascular system. Dehydration can also make people more prone to blood clots.
Older adults, pregnant people and newborns are among the most vulnerable to heat-related illnesses and death.
China also hit by extreme heat — and flooding
BEIJING — China is being buffeted by two weather extremes, with heavy rain and flooding forcing the evacuation of tens of thousands of people in the south and a heat wave prompting fears of a drought for farmers in the north.
At least one person has died in the flooding. The body of a student who fell into a swollen river in the southern city of Guilin was found two days later Saturday, state broadcaster CCTV said in an online report. Elsewhere in the Guangxi region, heavy rains flooded homes in some villages.
To the east, landslides and flooding hit parts of Fujian province, and 36,000 people have been moved, according to state media. A landslide trapped a truck in Songxi county, and videos posted online by the Quanzhou government showed vehicles inundated with muddy floodwater in a part of the historic city.
The Chinese government has issued repeated calls to step up disaster prevention and preparedness in anticipation of more severe weather events because of climate change. Violent rain and hailstorms killed seven people in eastern China’s Jiangxi province this year.
Much of northern China, including the capital, Beijing, has endured high temperatures for the past week.
Major heat wave to hit Midwest and East Coast, bringing heat alerts to 66 million
The summer is coming in hot: As Thursday’s solstice approaches, a heat wave is hitting the East Coast and the Midwest and is expected to last through at least Friday.
Almost 66 million people across the U.S. were under some level of heat alert yesterday afternoon. Heat warnings, watches or advisories were in effect from Iowa to Maine, affecting Detroit, Cleveland, Cincinnati, Pittsburgh, Philadelphia, Boston, New York and other cities.
“The duration of this heat wave is notable and potentially the longest experienced in decades for some locations,” the Weather Prediction Center said Sunday.