Sign up for our daily briefing

Make your busy days simpler with the Axios AM and PM newsletters. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to the Axios Closer newsletter for insights into the day’s business news and trends and why they matter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios Pro Rata

Dive into the world of dealmakers across VC, PE and M&A with Axios Pro Rata. Delivered daily to your inbox by Dan Primack and Kia Kokalitcheva.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with the Axios Sports newsletter. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with the Axios Des Moines newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with the Axios Tampa Bay newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Nashville news?

Get a daily digest of the most important stories affecting your hometown with the Axios Nashville newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Columbus news?

Get a daily digest of the most important stories affecting your hometown with the Axios Columbus newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Dallas news?

Get a daily digest of the most important stories affecting your hometown with the Axios Dallas newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Austin news?

Get a daily digest of the most important stories affecting your hometown with the Axios Austin newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Atlanta news?

Get a daily digest of the most important stories affecting your hometown with the Axios Atlanta newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Philadelphia news?

Get a daily digest of the most important stories affecting your hometown with the Axios Philadelphia newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Chicago news?

Get a daily digest of the most important stories affecting your hometown with the Axios Chicago newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top DC news?

Get a daily digest of the most important stories affecting your hometown with the Axios DC newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Eduardo Velev cools off in the spray of a fire hydrant during a heatwave on July 1, 2018 in Philadelphia, Pennsylvania. Credit: Jessica Kourkounis/Getty Images

Extreme heat and humidity will continue through the end of the holiday week across the eastern U.S., before it shifts westward, roasting the Midwest and Great Plains, potentially setting records and intensifying ongoing wildfires all the way to California.

Why it matters: Heat is the top weather killer in the U.S. during most years. According to the Centers for Disease Control and Prevention, more than 600 people are killed every year due to heat-related illnesses in the U.S.

Details: Shortly before noon on Monday, the heat index — which is a combination of the air temperature and humidity — in Washington, D.C. had already surged past 100 degrees Fahrenheit. Same for Philadelphia, Baltimore and parts of New York City. The air temperature is forecast to flirt with the century mark from Albany, New York to New York City southward to Washington, with heat indices reaching as high as 110 degrees Fahrenheit or higher, prompting the National Weather Service to issue excessive heat warnings.

Animation showing the heat dome (as indicated by 500 millibar height anomalies) located over the Northeast on Monday, and then shifting West over time. Credit: tropicaltidbits.com/European model.

Historical context: The actual air temperatures during this heat wave are not smashing all-time records in most cases, since they're only 10 to 20 degrees Fahrenheit above average for this time of year. However, the combination of heat and humidity, plus the long duration of this event, make it a public health threat.

  • Daily high temperature records have fallen in some places, along with records for the highest overnight low temperature.
  • Research has shown when air temperatures fail to cool below about 80 degrees Fahrenheit overnight, the risk of heat-related illnesses, including heat stroke, increases.
  • On Sunday night into Monday morning, the temperature failed to drop below that 80-degree threshold in New York City and other locations along the East Coast.

What's next: The heat should peak along the East Coast on Monday, but high temperatures all week are likely to reach or exceed 90 degrees Fahrenheit from the Mid-Atlantic to New England, which may put this event in the top 10 for long duration heat events.

Meteorologists define heat waves as occurring once the temperature hits or goes above 90 degrees for at least three consecutive days. Many locations in the East are on their fourth or fifth such day as of Monday, with no relief expected until next weekend.

The big picture: This heat wave has been triggered by an unusually intense, sprawling area of high pressure, also known as a "heat dome," that is parked across the eastern third of the nation. The clockwise flow of air around it is drawing hot, sultry air northward from the Gulf of Mexico, bringing unusually humid conditions as far north as Quebec and Ontario. This high pressure area is expected to slide to the west with time, ensuring that much of the lower 48 states eventually experience this event.

  • For the period of June 21 through June 29, as the heat wave was beginning, the U.S. set or tied 165 record high temperatures, along with 411 record warm overnight low temperatures.
  • This compared to just 62 daily record cold temperatures and 36 record lows during the same period.

Be smart: Peer reviewed studies show that heat waves are already becoming more likely and more intense across the globe as the overall climate warms due to rising amounts of greenhouse gases in the air. The connection between global warming and heat waves is the best understood and least controversial of any type of extreme weather events. One trend that's been most closely tied to climate change is an increase in overnight low temperatures.

Go deeper:

Go deeper

5 mins ago - Technology

Ex-N.Y. Post digital chief files lawsuit alleging sexual harassment

Richard B. Levine) (Photo by Richard Levine/Corbis via Getty Images

Former New York Post editor Michelle Gotthelf is suing her former employer, its parent company News Corp. and two editors, alleging she was reprimanded after complaining to senior executives that she was sexually harassed by retired N.Y. Post editor-in-chief Col Allan. The N.Y. Post issued a statement denying any wrongdoing.

Why it matters: "I felt that I owed it to myself and I owed it to the news organization and the people who answered to me," Gotthelf, who was a long time editor at the N.Y. Post, told Axios in an interview.

Updated 2 hours ago - Politics & Policy

Political consultants pocket taxpayer cash

Illustration: Shoshana Gordon/Axios

Members of Congress are turning to the same political consultants who got them elected to blast out taxpayer-funded communications from their government offices, records show.

Why it matters: While those members are barred from politicking with official funds, the firms have expertise in boosting elected officials' images for political gain and are in high demand for both campaign and government work.

Updated 3 hours ago - Politics & Policy

Omicron dashboard

Illustration: Brendan Lynch/Axios

  1. Health: Transplants rebound from COVID lull
  2. Vaccines: WHO: No evidence that healthy children, teens need boosters — Kids' COVID vaccination rates are particularly low in rural America
  3. Politics: Government website for free COVID tests launches early
  4. World: Greece imposes vaccine mandate for people 60 and older
  5. Variant tracker