TheClimateChanger

Digging a little deeper into the contiguous U.S. data, Louisiana had its hottest summer on record. Texas and Florida both had their 2nd hottest summers on record. The hottest summer on record in Texas was 2011 and the hottest summer on record in Florida was 1998. New Mexico had its third hottest summer on record, behind only 2011 and 2020. Only 5 states were cooler than the 20th century mean (Indiana, Ohio, Kentucky, West Virginia and Tennessee).

With today's data release, NOAA's NCEI has confirmed this to be the 15th warmest summer on record nationally, with a nationwide mean temperature of 73.01F - placing slightly ahead of 1933 and just a hair behind 2007. As noted, only three summers of the 20th century were warmer (1934, 1936 & 1988). National Time Series | Climate at a Glance | National Centers for Environmental Information (NCEI) (noaa.gov)

August was the 9th warmest on record nationwide, with meteorological summer coming in 15th place. While the final ranking is not terribly impressive, it's important to note that only three summers of the 20th century were warmer than this summer nationally (1934, 1936 & 1988).

For more context, the HO-83 artificially inflated daytime maxima by up to 2C in the southwest US on sunny days with light winds (the kind of days characteristic of a place like Tuscon). 2C is huge... it's possible with current instrumentation, there may have only been 4-6 days of 110F+ in those summers. So this is incredibly impressive to be blowing away these old records like this. The HO-83 Hygro- thermometer « Climate AuditThe HO-83 Hygro- thermometer « Climate Audit Inside the HO83 Hygrothermometer « Climate Audit Note: I don't normally link to Climate Audit, but they had some excellent information on this bias in 2007/2008, with a number of links to scientific papers exploring the issue. Their angle was the recent warming was biased by this issue, but obviously time has shown this to be nonsense as it has continued to warm even with improved instrumentation. Of course, as they noted, these ASOS sites are only about 5% of the USHCN sites, so it was a negligible issue to begin with. With that said, it does give reason to be a bit skeptical of some of the extreme heat records set in that era, and there were a number of them.

@donsutherland1 Wow, and the earlier records are likely illegitimate. See 1991 New York Times article on the erroneous temperature readings from the faulty HO-83 hygrothermometer in Tuscon during that era: In Tucson, It's Not the Heat, It's the Thermometers - The New York Times (nytimes.com) This would be like someone not only breaking the baseball steroid-era home run records, but knocking 100 out of the park.

Can you imagine if CXY was still the official observation site like it was in 1961? Looks like CXY is averaging 80.3F so far this month. Wow.

There's no way that's set back anywhere near four times the height of those trees.

Not only that, but you have to question the "statistical tests" he did to confirm the compatibility of his numbers with those of Coatesville and earlier sites in the county. Difference between these numbers for JJA and those for PHL in recent decades: 1982: PHL was 73.0, or 3.2 warmer 1985: PHL was 72.8, or 3.0 warmer 1986: PHL was 75.3, or 3.8 warmer 1992: PHL was 73.9, or 4.9 warmer 1997: PHL was 74.1, or 3.6 warmer 2000: PHL was 73.5, or 3.1 warmer 2004: PHL was 74.4, or 4.0 warmer 2009: PHL was 75.1, or 5.1 warmer 2014: PHL was 75.7, or 6.0 warmer 2023: PHL was 75.8, or 5.5 warmer In the years shown from 1982 to 2004, PHL averaged 3.7F warmer than the co-op site. In the three years since (2009, 2014, 2023), PHL has averaged 5.5F warmer than his figures for East Nantmeal. The only year somewhat comparable difference is 1992, when PHL averaged 4.9F warmer than the co-op site. I suspect that is related to the warm-biased HO-83 hygrothermometer that was in use at first order sites at the time. Since he's started adding his observations to create an "official" time series, the difference between the sites has jumped nearly 2.0F. Obviously, there was no massive increase in UHI in a single year. This would not pass any legitimate statistical scrutiny. If you use the real numbers, the trend is largely the same in recent decades.

Very hit or miss. Nothing in my neighborhood this evening.

Also, when I look at the most recent 14 years (2010-2023), I find a significant warming trend in daily maximum temperatures at Omaha - particularly in June. This is preferable for analysis, since this is the timeframe when the global warming signal just started overwhelming everything else. Compared to 1961-1990, the June maximum over the last 14 years is 2.7F warmer; the July maximum is 0.8F warmer; and the August maximum is 1.3F warmer. Looking at your data for 1991-2020, which shows minimal warming, I would say a linear trend is not a good approximation. This is a hockey stick pattern, with little warming over decades followed by rapid heating in the past 15 years.

The map posted by Brian Brettschneider is mean temperature, not average maximum. Both Des Moines and Omaha have very closely aligned trends and have warmed around 2F in the summertime just over the past couple of decades. The map shows little to no trend in that region. Given the trends match almost exactly, it would appear to be a regionwide warming and not something specific to either site. These are first-order stations that have been in the same location for decades, in two quiet cities that haven't experienced any population growth or significant increase in urbanization since the late 20th century, ruling out the possibility of urban heating effects. Maybe there's no trend if you are taking temperature in the middle of a cornfield, but that's not how the temperature is supposed to be recorded. Could be impacts from shading or improper exposure, similar to New York City's Central Park, which shows smaller warming trends than surrounding areas?

The alleged cool zone doesn't withstand scrutiny. It's warming rapidly in those areas in the summertime at official, first order NWS observation sites.

Des Moines, IA Relative to 1961-1990, the last 14 years at Des Moines have averaged 2.8F warmer in June, 1.2F warmer in July, and 1.7F warmer in August [+2.9, +1.6, +1.7, respectively, compared to 1951-1980].

I just don't buy it. The missing warming just seems to be bad data. The official NWS stations show plenty of warming. Omaha, NE Relative to 1961-1990, the last 14 years at Omaha have averaged 2.9F warmer in June, 1.2F warmer in July, and 1.8F warmer in August.

I remember 10-15 years ago the Union of Concerned Scientists came out with a projection for future climate changes, and @michsnowfreak wasn't having it. So I wanted to take a closer look at southeast Michigan to see how we're doing there, and, boy, it's not looking good. Toledo, Ohio (1961-1990) Findlay, Ohio (1961-1990) Flint, Michigan (2010-2023) The last 14 years at Flint, Michigan have averaged 0.6F, 1.1F, and 0.9F warmer than the 1961-1990 normal at Toledo, Ohio; and -0.4F, +0.3F, and +0.2F compared to the 1961-1990 normal at Findlay, Ohio in JJA. So Flint's summertime climate is now slightly warmer than the late 20th century climate of Findlay, Ohio, nearly a degree warmer than that of Toledo, Ohio, and only about a degree cooler than that of Columbus, Ohio (not shown). Dayton, Ohio (1961-1990) Cincinnati, Ohio (1961-1990) Detroit, Michigan (2010-2023) The last 14 years at in the Motor City have averaged -0.1F, +0.9F, and +0.9F in JJA compared to late 20th century Dayton, Ohio, and -0.8F, 0.0F, and -0.4F in JJA compared to late 20th century Cincinnati. So Detroit's summertime climate is now on par with the climate of the late 20th century is far southwestern parts of the State of Ohio (a tad warmer than Dayton, ever so slightly cooler than Cincy) and extreme northern Kentucky (CVG is across the border in Kentucky). Verdict The Union of Concerned Scientists' forecast has done incredibly well, but the low emissions forecast for 2050s looks too conservative. Probably in between low and high emissions at the moment. The near-term prognostication looks very good.

How are the Mississippi River levels holding up? I know things got very low late last summer and autumn.

But in any event, if you are in northern or central Virginia, at a constant elevation, you now need to be in south central Pennsylvania to experience your normal late 20th century climate. We can see the mean temperatures at Harrisburg/Middleton Area, Pennsylvania, are now in between those of Sterling/Dulles Area, Virginia and Charlottesville, Virginia from the late 20th century. In another decade or so, you will probably need to be in Williamsport or Scranton, PA, to experience a typical late 20th century Virginian climate, and by 2050, maybe Syracuse? I mean from the data I posted above Scranton is only about 2 degrees cooler than Sterling, Virginia (1961-1990) and the warmest years are already approaching Sterling's mean. Williamsport is even warmer being at a lower elevation. Harrisburg/Middleton, PA (2010-2022) Sterling/Dulles, VA (1962-1990) Charlottesville, VA (1961-1990)

Also, note I am using 1961-1990 mean since these give a good picture of the late 20th century climate many of us were familiar with when weather forums came about. These were the normals through 2000 and into 2001 until they were eventually replaced with 1971-2000 normals. The past decade and a half has seen the apparent climate for every location in the eastern U.S. shifted about 150-300 miles south compared to what was considered normal in the late 20th century. Somebody might say we need 30 years to do this analysis, but if I was a betting man, I'd certainly wager that the numbers will only get progressively worse over time.

Here is the same comparison with Albany, New York. Mean temperature for 2010-2022 is 49.9, compared to 47.2 for 1961-1990. Again, the coldest year since 2010 is warmer than the late 20th century mean. Average seasonal snowfall for 2009-10 through 2022-23 is 54.5 inches, which is down about a foot from the 1960-61 through 1989-90 mean of 66.2 inches. And here is Scranton, Pennsylvania: Mean temperature for 2010-2022 is 51.7F, compared to 49.1F for 1961-1990. Yet again, we see the coldest year since 2010 is warmer than the 1961-1990 mean. Snowfall for the period 2009-10 through 2022-23 is down about 20% from 1961-1990 mean

Using annual temperatures oversimplifies things a bit. By annual mean, over the past 14 years, temperatures at Burlington, Vermont are now warmer than the annual mean temperatures of late 20th century (1961-1990) Albany, New York, and approaching that of Scranton, Pennsylvania. However, the winters are still much snowier than the latter two locations. Part of it is the winters are significantly colder than Scranton, but they are actually milder than late 20th century norms at Albany. Despite winter temperatures averaging some 5 degrees warmer than 1961-1990, there's been almost no drop in seasonal snowfall yet. Burlington, Vermont (2010-2022) (2023 not included, but running even warmer than these values) Mean Temperature Mean Snowfall (2009-10 through 2022-23) Burlington, Vermont (1961-1990) -- Note that the coldest year since 2010 is an unbelievable 2.1F warmer than the 30-year average from 1961-1990 Mean Temperature (1961-1990) Snowfall (1960-61 through 1989-1990) Albany, New York (1961-1990) Mean Temperature (1961-1990) Snowfall (1960/61 - 1989/90) Scranton, PA (1961-1990) Mean Temperature (1961-1990) Snowfall (1960/61 - 1989/90)

Should IAD reach 99 or better today, that would tie July 2012, July 2011, July 1993, and July 1986, for second most 99+ readings in a month. The most is 5, set in July 1988. Looking through the records, the only periods with 3 consecutive days with highs at or above 99 that I could find were July 5-7, 1986 (99, 100, 99); July 8-10, 1993 (100, 99, 99); July 21-23, 2011 (100, 105, 99); and August 11-13, 2021 (99, 100, 99). There do not appear to be any recorded stretches of 4 or more consecutive days at or above 99F, so if it reaches 99F or better today, that would be the first time 4 consecutive days have occurred.

At Burlington, the past 13 years (2010-2022) have averaged almost 4 degrees warmer than the 1961-1990 mean. The coldest year of the past 13 is nearly 2 degrees warmer than the 1961-1990 average. Once 2023 (currently 2nd warmest on record) gets added into the mix, these numbers will go even higher! The 1961-1990 averages were what was considered normal as recently as 2000 and 2001. The last 13, going on 14, years are now warmer than the late 20th century (1961-1990) climate of Albany, New York (mean: 47.5), and approaching that of Scranton, Pennsylvania (mean: 49.1). In just two decades, the climate of Burlington, Vermont has teleported hundreds of miles south and is now on par with a late 20th century climate of southern New York and northeast Pennsylvania. And I'm not playing games by comparing it with mountains at a lower latitude. I'm strictly using low elevation sites for a fair comparison. I mean this is just incredible... the coldest June, August, September, and October of the past 13 years is warmer than the mean from 1961-1990. The coldest July of the past 13 years is just 0.2 degrees below the 1961-1990 mean, while the coldest December is only 0.6F cooler than the 1961-1990 mean. The lying press won't report this. You won't hear the news reporting that temperatures in lower elevations of Vermont are now comparable to what was considered normal in Pennsylvania just a couple decades ago. This is what a climate emergency looks like. Burlington, Vermont (1961-1990) Burlington, Vermont (2010-2022)

Running the same exercise for a place like DuBois, we see the climate there is now equivalent to that of late 20th century Elkins, West Virginia. Again, this is maintaining roughly constant elevation, with DUJ being at 1800' and EKN at 1900'. From 2010-2023, DUJ averaged 50.7F for the January to August time frame. From 1961-1990, EKN averaged 50.7F for the January to August time frame.

I always prefer to look at things in terms of latitude. Over the last 14 years, the January - August period has averaged 56.9F at Harrisburg. That's roughly in between the January - August average for Sterling (Dulles Airport), VA, in suburban Washington, D.C., and Charlottesville, VA, over the 1961-1990 climate period. From 1961-1990, Dulles (IAD) averaged 55.5F, or 1.3F cooler than Harrisburg over the past 14 years, while Charlottesville (CHO) averaged 58.4F, or 1.5F warmer than Harrisburg over the past 14 years. So Harrisburg's climate over the past decade and a half is now roughly equivalent to the late 20th century climate for northern Virginia, bordering on a central Virginian climate (at constant altitude).