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Heat Wave Bears Down On U.S.

Jul 17, 2013
Originally published on July 17, 2013 2:05 pm

The first big heat wave of the summer is here, bearing down on all parts of the U.S., following temperatures that blistered the West Coast in June.

Typically heat waves occur twice every summer. Meteorology director Jeff Masters of Weather Underground says expect the current bout of oppressive heat to last a bit longer than the usual three days. Look for relief by Saturday.

Heat wave highlights

Temperatures in the Northeast are 5 to 10 degrees above normal, with New York City experiencing the highest above-normal temperatures of any place in the country.

The hottest summer in U.S. history – an average 73.83 degrees for the season – occurred during the Dust Bowl in 1936. The 2011 and 2012 summers tied for second hottest but were only one-tenth of a degree cooler than the record.

Odd behavior

While the Northeast is burning up, Texas and Oklahoma recorded their all-time lowest temperatures for July 15.

And in parts of Alaska, the readings were warmer Monday than parts of Texas. Alaska’s eastern interior was in the low 80s, while Abeline, Texas, recorded a cool 68 degrees.

Baseball’s hot air stats

It is not a myth but a matter of physics that baseballs fly farther in hot, humid air.

Physics professor Alan Nathan of the University of Illinois at Urbana-Champaign, explains. “The higher the temperature, the less air resistance, so the ball flies farther.”

Each increase in temperature by 10 degrees can increase the flight of a ball by 2 1/2 to 3 feet. A ball hit during the heat wave could fly 15 feet farther than a ball hit in 40-degree weather in, say, April in Chicago.

Hot phones not so smart

Most smartphones are designed to withstand extreme temperatures – many of them shut themselves down when they sense too much heat. But the batteries that power phones are still fairly vulnerable.

Engineering professor Yury Gogotsi at Drexel University says high temperatures can cause batteries to die faster than normal and can lower a battery’s life expectancy.


  • Chris Vaccaro, meteorologist and spokesman for the National Weather Service.
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From NPR and WBUR Boston, I'm Jeremy Hobson.


I'm Robin Young. It's HERE AND NOW. In a moment, our conversation with bestselling author Khaled Hosseini.

HOBSON: But first the big heat wave that is going on right now, the first big one of the summer, has officially hit. New York City is shoring up for possible record-breaking power demands. Chicago is bracing for a heat index of 106 degrees. And residents of Prince George's County, Maryland, just outside D.C., are trying to stay cool as crews repair a failing water main.

Tominetta Stamp(ph) told ABC news she was filling her recycling bins with a garden hose.

TOMINETTA STAMP: Luckily the electricity is on, but water, you cannot do without water.

HOBSON: You cannot do without water. Well, joining us now for more on the heat wave is Chris Vaccaro with the National Weather Service. And Chris, first just give us a sense of the scope of this.

CHRIS VACCARO: We have high heat and humidity dominating the eastern third of the United States. It's a very large area of high pressure that is pumping in very warm, moist, tropical air up into the northern latitudes, and we're seeing high heat build, as well. And that combination of high heat and humidity are creating some dangerous conditions, especially in northern areas that are not accustomed to such high heat.

HOBSON: And is this something that we would see every few years, every 10 years, more infrequently than that?

VACCARO: This is somewhat typical of late July. We have been seeing some record high temperatures, especially in areas closer to the Canadian border. Burlington, Vermont, for example had - tied a record high temperature of 93 degrees. So you have to go closer to the Canadian border, where temperatures are setting records.

Further south, we've seen hotter temperatures in the past, but still when you factor in the heat in the 90s and the high humidity, it's still dangerous. And this is still one of the most significant heat waves of the season so far.

HOBSON: And you're saying that high pressure is a big part of this. I guess there are going to be a lot of people wondering whether climate change has something to do with this.

VACCARO: Well, you know, under continued climate change, we would expect to have more severe and more prolonged heat waves, as we've seen in prior years, where we've had triple-digit heat just encompass large parts of the United States. But this heat wave is somewhat more typical of what you would expect in late July.

But again, just because it's typical or standard doesn't mean it's any less dangerous, and people need to be able to stay cool and stay hydrated and stay out of the direct sun and preferably stay indoors during the next few days as this heat wave continues on.

HOBSON: Just certain people, or do you think all people need to stay indoors as much as possible?

VACCARO: This heat wave has the ability to impact several concentrations of the public. Certainly the elderly are at risk. Outdoor workers are at risk. You should limit your exposure to direct sun, seek air conditioning, seek a cooling shelter. And the heat is not just dangerous during the daytime. It's also dangerous at night, and that combination takes a toll on the human body, and that can cause health hazards.

HOBSON: We often hear when it gets this hot that air quality is affected. How might that be affected in this heat wave?

VACCARO: Right, in certain areas, especially in the Mid-Atlantic region, parts of D.C., Baltimore, into Southern New Jersey, there are air quality alerts that have been issued by local authorities, where pollutants are being trapped. We have a very strong area of high pressure that is limiting the air from circulating closer to the ground.

So for those with any breathing issues or health issues in that capacity, it can have some health issues this - coming days.

HOBSON: You know, one of the things I've noticed this summer is that even when thunderstorms come through, it doesn't necessarily get cooler right after that. When is this heat wave going to be over with?

VACCARO: The heat release begins somewhat tomorrow, and into Friday in the Upper Midwest. The cold front goes into Minnesota and Wisconsin and the western parts of the Great Lakes tomorrow, with the threat of severe thunderstorms. It continues eastward into Michigan, the Ohio Valley and the eastern Great Lakes on Friday and then into Saturday into parts of the Northeast and Mid-Atlantic.

So it will be a three-day progression of a cold front that will usher in cooler, dryer air but at the cost of severe thunderstorms with potentially damaging winds and also the threat of heavy rainfall.

HOBSON: And Chris, in the meantime, as you've been looking at the maps, is there any place in the country that's cool right now?

VACCARO: Ironically you'll have to go down to West Texas and New Mexico for some cool weather. There's an area of low pressure that is trapped over that region, just as the area of high pressure and the heat wave is trapped over the eastern third of the United States, which has in some sense brought much needed rainfall to those drought-stricken areas.

However, in some cases too much rain is falling too soon, and we are seeing flash flood watches and warnings.

HOBSON: Chris Vaccaro with the National Weather Service, thanks so much.

VACCARO: Thank you. Transcript provided by NPR, Copyright NPR.