--- title: Heat Wave: President Obama Warns of Excessive Heat description: President Obama warned Americans to stay safe during an ongoing heat wave as heat advisories remained in effect in at least 15 states canonical: https://time.com/4416812/heat-wave-warning-obama/ author: Justin Worland article:opinion: false article:content_tier: free article:published_time: 2016-07-21T13:31:20.000Z article:modified_time: 2026-02-22T23:25:59.741Z article:section: Science og:title: Heat Wave: President Obama Warns of Excessive Heat og:description: President Obama warned Americans to stay safe during an ongoing heat wave as heat advisories remained in effect in at least 15 states og:url: https://time.com/4416812/heat-wave-warning-obama/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt943eca9f79024fd1/69889d04a988ca57e16b8b6c/heat-map.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: heat-map og:type: article twitter:card: summary_large_image twitter:title: Heat Wave: President Obama Warns of Excessive Heat twitter:description: President Obama warned Americans to stay safe during an ongoing heat wave as heat advisories remained in effect in at least 15 states twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt943eca9f79024fd1/69889d04a988ca57e16b8b6c/heat-map.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  # President Obama Warns of Excessive Heat as Temperatures Expected to Top 110  by [Justin Worland](/author/justin-worland/)  ## Justin Worland Senior Correspondent Jul 21, 2016 1:31 PM CUT  NOAA/NWS  by [Justin Worland](/author/justin-worland/)  ## Justin Worland Senior Correspondent Jul 21, 2016 1:31 PM CUT President Obama warned Americans to stay safe during an [ongoing heat wave](http://time.com/4406219/weather-forecast-heat-wave/ "undefined") as heat advisories remained in effect in at least 15 states and some places braced for temperatures that could top 110°F. [Advisories](http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=usa&wwa=heat%20advisory "undefined") in effect Thursday from the National Weather Service warned residents across the Midwest and South to stay in cool locations and remain hydrated. The heat index—a measure incorporating heat and humidity—is expected to exceed 105°F in the majority of those places. Extreme heat could spread to parts of the Eastern seaboard over the weekend. President Obama was [briefed](https://twitter.com/WhiteHouse/status/755808216001294336 "undefined") on the coming heat wave by his chief science advisor John Holdren earlier this week, according to the White House. “Stay safe as it heats up: Drink water, stay out of the sun, and check on your neighbor,” Obama [said](https://twitter.com/POTUS/status/755803507760902144/photo/1 "undefined") on Twitter. This week’s [heat wave](http://time.com/4411768/heat-dome-heat-wave-summer-weather/?iid=sr-link1 "undefined")—the biggest to hit this year—was caused by a high pressure system known colloquially as a heat dome that traps heat close to the Earth’s surface. The high temperatures could stretch from as far southwest as Southern California to the Northeast. “There’s a very large bubble that’s working its way across the nation,” said Sean Sublette, a meteorologist at Climate Central, [earlier this week](http://time.com/4411768/heat-dome-heat-wave-summer-weather/?iid=sr-link1 "undefined"). “The atmosphere travels in waves—waves that are up and waves that are down. Up waves are allowing a lot of hot air to come up through the equator.” This heat wave contributes to the likelihood that this year will be the warmest on record. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4416812/heat-wave-warning-obama/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4416812/heat-wave-warning-obama/"},"headline":"President Obama Warns of Excessive Heat as Temperatures Expected to Top 110","datePublished":"2016-07-21T13:31:20.000Z","dateModified":"2026-02-22T23:25:59.741Z","description":"Heat advisories remained in effect in at least 15 states","url":"https://time.com/4416812/heat-wave-warning-obama/","keywords":["weather"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt943eca9f79024fd1/69889d04a988ca57e16b8b6c/heat-map.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Justin Worland","jobTitle":"Senior Correspondent","url":"https://time.com/author/justin-worland/"}],"articleSection":"Science","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt943eca9f79024fd1/69889d04a988ca57e16b8b6c/heat-map.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"heat-map","caption":"","creditText":"NOAA/NWS","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/science/","name":"Science"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/weather/","name":"weather"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4416812/heat-wave-warning-obama/","name":"President Obama Warns of Excessive Heat as Temperatures Expected to Top 110"}}]}] ```