Media Chases ‘Climate Enhanced’ Heat Waves, Misses Data Showing They are Less Frequent

Originally posted at ClimateREALISM

A number of media outlets are claiming that U.S. heatwaves are getting worse this week due to climate change. This is false. Actual data from temperature measurements show that heatwaves in the U.S. are on the decline even as climate change has occurred over the last 75 years.

It is summer in the Northern Hemisphere, and unsurprisingly to those that pay attention to data, it is hot in many places in the U.S. – in other words, business as usual for summer. But, the media sees climate change in every heatwave event, and seeks to exploit a connection, even though one doesn’t exist. For example, last week it was declared that the world had seen its hottest day ever on July 4, with some outlets claiming the “hottest in 100,000 years.” That of course, was proven laughably false here at Climate Realism on both counts.

This week, the media was at it again. The Washington Post, in an article titled, “Relentless heat wave reaching maximum strength: Weather updates,” says this:

“What is a heat dome? Understand the science and how drought and climate change make them worse.”

Axios, in the article “What this summer’s weather reveals about climate change” written by the ever-excitable Andrew Freedman, opines,

Monitoring the planet’s climate this summer can give one the impression that the climate system — which includes the oceans, atmosphere, ice sheets and more — has gone off the rails.

Climate studies have warned about an uptick in simultaneous heat waves occurring in the Northern Hemisphere.”

Then there is the “World Socialist Web Site”, with the headline: “Record-breaking US heat wave demonstrates the growing dangers of climate change.

None of the news outlets running heat wave stories this week examined or cites historical data on heat waves, preferring instead to push scary numbers in the form of heat indexes that combine temperature and humidity, reprint the opinion of “climate scientists,” and reference computer models that suggest climate change is making heat waves worse.

Yet, data exists, for any reporter with a modicum of journalistic curiosity to find. The problem is that the data doesn’t look scary.

The U.S. Environmental Protection Agency (EPA) maintains a web page on heatwaves in the U.S. which contains some very interesting data and maps. Despite the claims of climate change creating worse heatwaves, the data the EPA has compiled going back to 1948 says exactly the opposite.

The data is on display in Figure 1, below.

Figure 1: This map shows trends in unusually hot temperatures at individual weather stations that have operated consistently since 1948. In this case, the term “unusually hot” refers to a daily maximum temperature that is hotter than the 95th percentile temperature during the 1948–2020 period. Thus, the maximum temperature on a particular day at a particular station would be considered “unusually hot” if it falls within the warmest 5 percent of measurements at that station during the 1948–2020 period. The map shows changes in the total number of days per year that were hotter than the 95th percentile. Red upward-pointing symbols show where these unusually hot days are becoming more common. Blue downward-pointing symbols show where unusually hot days are becoming less common. Data source: NOAA, 2021, EPA

The EPA writes:

The data come from thousands of weather stations across the United States. National patterns can be determined by dividing the country into a grid and examining the data for one station in each cell of the grid. This method ensures that the results are not biased toward regions that happen to have many stations close together.

[Figure 1] was created by reviewing all daily maximum temperatures from 1948 to 2020 and identifying the 95th percentile temperature (a temperature that one would only expect to exceed in five days out of every 100) at each station. Next, for each year, the total number of days with maximum temperatures higher than the 95th percentile (that is, unusually hot days) was determined. The map shows how the total number of unusually hot days per year at each station has changed over time.

The EPA’s data for 1,066 weather stations across the United States showed a total of 863 stations, or 81 percent, reporting either a decrease or no change in the number of unusually hot days. By comparison, only 19 percent of all weather stations reported an increase in the number of unusually hot days since 1948.

Many of the stations showing hotter temperatures over the 1948-2020 period were located at airports or otherwise badly sited locations that created heat biases such as reported by the study Climate Realism covered last year, Corrupted Climate Stations: The U.S. Temperature Record Remains Fatally Flawed. As reported in that study, much of the upward heat bias occurs in the minimum overnight temperature at these weather stations, enabling them to reach higher than expected daytime high temperatures had they not had a “head start” from the warmer than expected overnight low.

In fact, you can see this issue on display using maximum and minimum data for all weather stations in the U.S. Figures 2A and 2B below show maximum and minimum temperatures in the U.S. from 1948, so that it matches the start of EPA data in Figure 1.

Figure 2A maximum temperatures in the U.S. since May 1948 to June 2023, 2B minimum temperatures in the U.S. since May 1948 to June 2023. Source: NOAA National Temperature Index plotter. Note: color of the maximum temperature series in 2A has been changed to red from blue to delineate the two sets of data.

In figure 2A, you can see the maximum temperatures (the sort of temperatures that would occur in a heat wave) have not changed much since 1948. In fact, there are spikes of high temperatures in the U.S. in 1954 and in 1963 that are higher than the present day.

In figure 2B, you can see the minimum temperatures have had a slow and steady rise since 1948, with peaks in the last 20 years (warmer nights) being higher than values in the 1940s and 1950s.

Finally, another graph from the EPA shows that heat waves were actually the worst for the U.S. in the 1930s, well before climate change became a blip on the media radar. See Figure 3.

Figure 3. This figure shows the annual values of the U.S. Heat Wave Index from 1895 to 2021. These data cover the contiguous 48 states. An index value of 0.2 (for example) could mean that 20 percent of the country experienced one heat wave, 10 percent of the country experienced two heat waves, or some other combination of frequency and area resulted in this value. Data source: Kunkel, 2022, EPA

The bottom line is this: despite what the media says, real-world data shows heat waves are NOT getting worse in the United States due to climate change. This flies in the face of opinions by climate scientists cited in the mainstream media which seems wedded to the narrative that climate change is causing a crisis, despite data to the contrary.

Anthony Watts

Anthony Watts is a senior fellow for environment and climate at The Heartland Institute. Watts has been in the weather business both in front of, and behind the camera as an on-air television meteorologist since 1978, and currently does daily radio forecasts. He has created weather graphics presentation systems for television, specialized weather instrumentation, as well as co-authored peer-reviewed papers on climate issues. He operates the most viewed website in the world on climate, the award-winning website

Learn more about heat and temperature at

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July 18, 2023 6:05 am

MSM aren’t missing it, they’re ignoring it – they have an agenda to meet

Reply to  Energywise
July 18, 2023 6:11 am

Someone gave them a red colored crayon and by God they are going to use it.

July 18, 2023 6:23 am

I regularly ride a bicycle for exercise and the joy of it. I have to thank Tony Heller partly for the inspiration to do this. He used to video many of his rides in and around Boulder and I decided to dust off an old bike to ride in many of the same places.

I’ve been doing this for a few years now. This activity has made my legs stronger and for it I’m a better skier also. Being outside, one gains a better appreciation for reality, like it gets hotter in summer and colder in winter. Riding around one also gets a better appreciation of how temperature actually varies by terrain in an area many times by several degrees within a matter of meters in distance.

Long story short, natural variability is much larger than the “change” we are being fed.

Reply to  Scissor
July 18, 2023 6:41 am

You have to view climate over millions of years – relying on a 10 year or so snap shot, is only useful if you have an agenda to peddle

Reply to  Energywise
July 18, 2023 7:45 am


I might be thinking of it incorrectly, but a 1C change in temp from one year to the next is not that unusual. A 1.5C trend change over a century is nothing. Now if that trend went up or down for a few hundred years, then the effects would be quite noticeable, but still not outside of the realm of nature.

Joseph Zorzin
Reply to  Energywise
July 18, 2023 8:04 am

I think they’re relying on more like a 10 day snap shot.

Joseph Zorzin
Reply to  Scissor
July 18, 2023 8:05 am

I worked outside for 50 years and agree completely. And I’ve been riding bikes all those years too!

D Boss
Reply to  Scissor
July 19, 2023 3:51 am

I totally agree, riding a bike gives you a visceral sense of rather large differences over small distances and varying ground cover. I ride at dawn – fewer idiots on the road and cooler here in S Florida. There is a 2-3 deg F drop when going from mostly condos/parking lots and few trees to a zone with mostly big old trees/grass in single family home zones.

Giving a first hand experience of what the UHI does over even very small distances. (~1/2 to 1 mile)

Tom Halla
July 18, 2023 6:49 am

Starting temperature graphs in 1948 is deliberately deceptive.

Reply to  Tom Halla
July 18, 2023 7:16 am

They are liars, lies are all they have.

Reply to  2hotel9
July 18, 2023 7:21 am

No, see my comment above.

Reply to  Tom Halla
July 18, 2023 7:21 am

Not in this case. The choice was a logical one, because this date represented the oldest date they could use that gave a representative sample of stations that had been in continuous operation.

Dave Fair
Reply to  Anthony Watts
July 18, 2023 10:29 pm

And you pointed out the severity of the early 20th Century heat waves compared to the recent ones; the whole picture, as it were, Anthony. Normal people reading the article will see that current heat waves are nothing compared to those in history. And when over 80% of the records are unchanged or declining, people get the proper idea.

Tom Abbott
Reply to  Dave Fair
July 19, 2023 5:19 am

I agree. Anyone reading this post should be convinced that all the doomsday talk of an overheating world is pure climate change propoganda.

We are not experiencing unprecedented heat or heatwaves. All one has to do to see this is look at the evidence, such as what is in this article.

Richard Page
July 18, 2023 6:57 am

Not just the US. Whilst Europe is having a nice warm Summer, the UK is experiencing a cold, wet July. More rain than the last couple of years and lower temperatures – warmest UK July temperature this year (so far) has been around 30°C. Not likely to let up before August, if then.

James Snook
Reply to  Richard Page
July 18, 2023 9:37 am

In Manchester it hasn’t even broken 20! Down to 16 at present (late afternoon) wearing a wool sweater and seriously considering turning the central heating on.

Great post Anthony, many thanks for your good work.

July 18, 2023 7:13 am

Hi Anthony,

I’ve noticed that here in Austin the Weather Service forecasts are consistently over-forecasting the same day’s high temperature by 3 to 5 degrees F! Yesterday, for example, the morning forecast for Austin was for a record 108 degrees when the actual high temperature ended up being 103. This is happening every day by at least 2 degrees F. I assume they are going with the high end of an estimated range rather than just plain exaggerating for the fear effect, and if challenged would likely say it is in the public interest to exaggerate the high temperature for safety reasons. But what is meteorological practice supposed to be when forecasting daily temps? Is there an uncertainty range in the models? If so, do they always only go with the high end of the range?

Reply to  Kasmir
July 18, 2023 4:07 pm

Because most of the Western world population are snowflakes, terrified by the prospect of being melted by a 1.5C increase in temperature.

Mark Luhman
Reply to  Kasmir
July 18, 2023 9:30 pm

Yes and when they don’t make the prediction they adjust the days data to match the predictions the next day. Somehow the automatic recording and display software need adjustments to what was automatic recorded.

July 18, 2023 7:15 am

They have not “missed” anything, media and academia are outright lying, with malice of forth thought they are lying to people. STOP giving them cover, Mr Watts! Call them what they are, blatant liars.

Richard Page
Reply to  2hotel9
July 18, 2023 11:49 am

Malice aforethought.

July 18, 2023 7:25 am

Is it “missing” when they don’t look?

Nicholas McGinley
July 18, 2023 7:33 am

News reporting about climate is just getting more and more inane.
It is no exaggeration to say it is a blizzard of bullshit.
This morning I came across a news item in which some people are saying that if present trends continue, sea level will rise over 30 feet by 2300, just over 75 years from now.

It is almost like they just make up whatever goofy nonsense pops into their heads.
Come to think of it, that is exactly what they do.

Hoyt Clagwell
Reply to  Nicholas McGinley
July 18, 2023 9:01 am

And I can’t tell you how many doomsday climate armageddon articles I come across every day where the author is complaining that “nobody is talking about it!”

Steve Case
Reply to  Nicholas McGinley
July 18, 2023 9:09 am

I’m sure you meant 2100 (-: A linky pooh to that news item would be great.

NOAA says:

“…the absolute global sea level rise is believed to be 1.7-1.8 millimeters/year.

30 feet (9144 mm) over the next 75 years comes to 122 mm/year.

Michael in Dublin
July 18, 2023 8:28 am

If the heat waves were increasing both in duration and frequency from year to year with no counterbalance outside of these times I would then begin to consider this a problem. Ireland has been interesting this year with summer arriving only in June only to be followed by a much cooler and very wet July. Yesterday I went out at 9h00 in shorts and was really cold – with wind chill about 8C.

Richard Page
Reply to  Michael in Dublin
July 19, 2023 3:29 am

Yup – ‘Global Warming’ would seem to imply that it was everywhere at once, not what we’ve had recently, which is varied weather patterns.

Danley B. Wolfe
July 18, 2023 9:14 am

I like the red/blue hotter/colder chart… clearly shows which areas are are truly changing. I think it would be cool to just get rid of Florida, Georgia, Florida, Lousisiana and Mississippi and the national average temperature would be just beautiful and the rest of us happy.

July 18, 2023 9:14 am

It’s funny looking at the photos accompanying the heatwave stories. It’s often of fires which have almost nothing to do with heatwaves.
The actual scene during a heatwave is most people staying indoors or heading to the beach or local pool. Nothing that could provide a match for the hysterical headlines.

There were articles about the death valley temperatures showing people grinning with the Furnace Creek sign and noting that the high temperatures were ATTRACTING tourists, lol.
The articles tried to say that was a ‘risk’ of climate change! People are being drawn like moths to a fire! How terrible for those poor smiling souls!!

Could the narrative be any more transparent? How could any adult fall for this?

I spent the first 10 years of my life in the Rub Al Khali desert in Saudi Arabia. Temperatures were typically in the mid-40s during the day, but no one even mentioned the heat because it was the same every day. What’s to talk about? It didn’t rain for years on end. It was definitely hot in the sun but fine in the shade or if you had some water to drink. Humans (and our predecessors) spent hundreds of thousands years living in these kind of temperatures WITHOUT ‘cooling centers’, ‘heat advisories’ or any form of electric fans or air conditioning.

We are now pampered with nearly 100% ideal and comfortable temperatures whenever we desire for most of the world’s population. And this happened within the last 60-80 years.
Please explain the crisis to me.

July 18, 2023 9:20 am

Climate Enhanced Story Tip

‘Underground climate change’ is deforming ground under Chicago buildings, report claims

The denser the city, the more intense is underground climate change.”

Richard Page
Reply to  strativarius
July 18, 2023 9:44 am

I don’t think ‘underground’ sources have much to do with it. UHI effect is likely transmitted into foundations as well as aboveground structures and the air in, around and above the urban area.

July 18, 2023 9:38 am

But why wouldn’t the Earth be warmer the next few years, Hunga Tonga blasted enough water vapor to the edge of space and increased the humidity of the Stratosphere by 10% and this was predicted.

Mike Maguire
July 18, 2023 10:54 am

Thanks, Anthony.

As you stated, overnight temps are the ones warming the most. Also the coldest places and driest places.

As your map of hotter days shows, it’s mainly the Western 1/3rd of the US that has had the increase(also some coastal cities in the East). Those are the driest places in the country.

In the Midwest, Summer daytime extreme heat has been greatly suppressed by massive evapotranspiration of the tightly packed corn plants, which have established a man made, beneficial micro climate across a dozen states during the growing season in the Cornbelt.

Desert Amplification in a Warming Climate

Screenshot 2023-07-18 at 12-42-51 Desert Amplification in a Warming Climate - Scientific Reports.png
Mike Maguire
Reply to  Mike Maguire
July 18, 2023 11:05 am

The last 30 years in the Cornbelt have featured the best growing season weather in our country’s recorded history.

July 18, 2023 11:52 am

Imagine being a reporter. Sitting every day in front of your screen, headset on, knowing that you are responsible for X number of stories, each with at least Y words. Your only sources are people you went to school with, press agents, people selling stuff and your family.

Science and technology are not subjects you know much about. You were an English (Journalism … Ecology … Romance Languages … Botany) major.

And your newspaper (TV station, blog …) is running out of subscribers, advertisers and readers.

And a press release comes across the screen saying, “Record Heat! The World Is Going to End! CO2!”

It’s a tough world out there. That’s a fact, not an excuse.

Tombstone Gabby
Reply to  rovingbroker
July 18, 2023 10:14 pm

G’Day rovingbroker,

Sitting every day in front of your screen…”

Do a quick re-write of a corporate handout, or get out and question/interview a number of knowledgeable sources. The pay remains the same.

July 18, 2023 12:54 pm

The story changes, the message is the same.

July 18, 2023 2:28 pm

It is winter down here in Australia’s Hunter Valley

Just out of bed catching up on the blogs, waiting for it to warm up a bit before the dog takes me for a walk.

Full on blue sky, about 10C outside, heater on, with a forecast max of only 18C, (doubt I will use the air-conditioner to cool it down to 15C global average though)

Tomorrow morning I suspect a late start, as it is forecasting 1.5C overnight. !

July 18, 2023 3:20 pm

Remember when climate was defined as 30 years of weather? I do. The weather must change for 30 years in order for climate to change. Cause and effect.

Paul Hurley
July 18, 2023 3:43 pm

They certainly enjoy their flashy colours.

Dave Fair
Reply to  Paul Hurley
July 19, 2023 9:47 am

My, how things change in five years: The temperatures are cooler but the colors and the babe are hotter!

July 18, 2023 3:50 pm

Thank you for this reality article, Anthony.
For additional support, heatwaves in Australia are equally ordinary.
The link below is for 8 of the biggest or significant cities in Australia for heatwave coverage where it matters to people. I use a simple definition of a heatwave – for example a 5-day heatwave at a location comes from 5 consecutive days of Tmax whose average temperature is the highest for the year. I show heatwaves of 1, 3, 5 and 10 days. Also shown are graphs for the Top 40 hottest heatwaves; and the graphs when the BOM ACORN-SAT adjusted temperatures are used. Some of the raw CDO graphs go back to the 1860s.
Summary. There is no credible evidence that our heatwaves are getting hotter or longer, unless you use adjusted data.
(Do allow for download time).
Geoff S

Reply to  sherro01
July 18, 2023 4:27 pm

Thanks for these graphics Geoff.

I reckon that a fair dinkum heatwave is a minimum of 3 days when the temperature hits 39C each day, and stays at that for at least three hours.

Jeez, as kids in the 50s, that kind of weather just meant we went swimming rather than play cricket.

old cocky
Reply to  Mr.
July 18, 2023 4:46 pm

3 days where it gets over 39? That’s October, isn’t it?

Reply to  old cocky
July 18, 2023 5:27 pm

Used to be.
Now all the blood-red and maroon colored weather maps start appearing in August.
When the forecast is for 25C max.

Dave Fair
Reply to  old cocky
July 19, 2023 9:57 am

On the flip side (here in Las Vegas) 39+℃ occurs beginning the early part of July and extending through the early part of September.

old cocky
Reply to  Dave Fair
July 19, 2023 2:16 pm

That seems a bit late. We can get hot from mid October through to late February (you’re used to it by then). Come to think of it, it was low 40s in March on a trip to Cowra some years back.

Walgett is a good example of inland NSW –

Tombstone Gabby
Reply to  Mr.
July 18, 2023 10:30 pm

G’Day Mr.,

Jeez, as kids in the 50s…”

40’s and 50’s in Brisbane. My only memories of ‘weather’: thunder storms with hail on a corrugated iron roof in summer, and cold westerly winds in winter. ‘Hot’ weather, probably had some, but nothing to stick in the memory.

Mark Luhman
July 18, 2023 9:28 pm

I am so tired of looking how the day turned for in the last 3 days display on the national weather site at 11:00 PM only to see different temperatures display the next day for that day and they are always up.

Leo Morgan
July 20, 2023 1:29 am

Anthony, I’m a long-term fan, and occasional commentator.
I’m reluctant to criticise you or your work. But Anthony, I’m troubled by this particular article. Accurate though the graph is, I still feel mislead.
Climate Change Indicators: Heat Waves | US EPA
As you can see from the link I provide, the data that you have presumably also seen indicates the EPA reports an ever-growing amount of heat waves since the 1960’s.
My “take-home” from your article is that the EPA claims heat waves are in fact reducing. I even went to tweet that claim in reply to an alarmist.
But I checked all the facts first and discovered I had formed a mistaken opinion as a result of your article.
Yes, your graph is accurate. Yet if you had even alluded to the other EPA data on the subject, I wouldn’t have been at risk of making an egregious mistake. It’s rare that I feel so completely mislead by WUWT. That sort of balance is what makes WUWT a reliable source.

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