TheClimateChanger

Yeah, I think there was a lot of deforestation in that era. Looking at old pictures of the city, and there is not a tree to be found. Whole hillsides just stripped barren. Must have been a lot of landslides and flash floods.

With the very warm lows, could be one of the hotter 4-day stretches in the month of June by mean temperature. These are the 10 highest 4-day mean temperatures in the threaded history. Last year's heat, while falling short of the early 99-101F type forecasts, was still one of the hottest 4-day stretches on record for June. 8th officially, but several of those are duplicates from heat waves that lasted more than 4 days, such that only 4 different years saw hotter 4-day means.

Speaking of volcanos... this looks promising:

I added a little context after your quote:

I think it probably depends on whether you are looking pre- or post-invention of air conditioning. Prior to the invention of air conditioning, I suspect something near pre-industrial is the optimum. Perhaps somewhat colder. Last glacial maximum is probably too cold due to the expansive continental ice shelves, although it would open up a lot of new coastlines. Ben Franklin considered 47-50F annual mean temperature to be the ideal for agriculture and industry. I think patterns of development [prior to air conditioning] support that, with large cities like Chicago, Detroit, New York, Boston, Pittsburgh, Cleveland, Buffalo, etc. falling in that isothermal band. The south was mostly underdeveloped rural/agrarian lifestyle. Maybe some winter homes in Florida. So, prior to the invention of air conditioning, you would probably want to find the climate regime that maximized the areal extent of mean temperatures from the mid 40s to low 50s. Of course, now, most of these places are above 50F in the running means. But he did say 50-53F was the second best temperature band.

Makes sense to me, and I've made this argument in the past. If you read weather records from that era, the general consensus was warming from past eras. I think this is supported by longer-range temperature records and reconstructions. But it does call into question the use of this era as some sort of special baseline. The true baseline may, in fact, have been a continuation of the natural cooling trend that had generally characterized the period since the Holocene Thermal Maximum - perhaps to levels even colder than those of the so-called Little Ice Age. Granted the degree of warming at that time was a tiny fraction of what we see today, so it wouldn't make a huge difference. But this paper would suggest the cumulative human impact is at least slightly higher than commonly reported from temperature datasets which use that period of history as the baseline of a natural climate.

Just ran that by it. It suggests a combination of temperatures near 110F, 75 mph winds and extremely low relatively humidity likely desiccated the crops. It suggests such conditions could wilt and brown the corn, causing drought or freeze-like damage to the crop. The strong winds would have also damaged the crop and caused more heat damage than would occur in a still atmosphere.

I ran this scenario by AI and it concluded the temperature could have reached no more than about 100-110F. It said the warming from a heat burst [compressional heating] would be no greater than the dry adiabatic warming rate, and that a surface temperature of 140F would require an upper atmospheric temperature that would be implausibly high. It suggested the burst thermometers were likely the result of instrument failure due to the sudden change in temperature. Not sure if any atmospheric scientist might want to weigh in.

You can see the rural effect warming in your data for Caribou, Maine as well. Another remote community near the Canadian border. Look at all those record-breaking June temps in recent years! The complete opposite of what the UHI lie would suggest!

I would argue it translated to the surface in 2022 & 2024, as well. If you look at Bradford, PA, useful as one of the more remote and sparsely populated locations, in the Eastern CONUS. We see it had never hit 90F in the month of June dating back to 1958 in the month of June prior to 2022. The monthly record of 89F was tied in 2021. In 2022, it reached 90F twice - including a record-breaking 93F on the 22nd. It reached 90F last June an incredible three times! Additionally, it reached 89F once each in 2022 & 2024 (the former monthly record high). Just an astounding run. I expect more record-breaking heat in the mountains of northern Pennsylvania with this upcoming heat ridge. What was once without precedence is now a yearly occurrence! I like to think of it as rural effect warming. Certain persons/entities claim warming is being enhanced or caused by a so-called urban heat island effect, but then when you look at the actual numbers, it's often the most remote locations breaking records all the time. So, the urban heating theory makes no sense. If anything, modern technology and siting/exposure standards are such that the UHI signal is less impactful as it was in the past.

Yeah, I doubt there's ever been a case where the entire region was AOA 100F on the same date.

Some scenes from the flash flood emergency on Sunday:

Looks increasingly likely that it turns hotter by Sunday. The NWS forecast has low 90s. I took a look at the most recent GFS run and, taken literally, it would suggest 90s Sunday-Friday. Obviously, not ready to commit to that forecast, but either way it should be a hot week. Hopefully, it will be drier as well, with all of the recent rainfall and flooding issues. A very soggy weekend for the US Open Championship at Oakmont.

I think the pitching is too good these days. The MLB keeps changing the game to drum up offense to make it more exciting, missing the fact that baseball is a 3-2 type game like they play in Japan. Now, they have pitch clocks, National League Designated Hitters, shortened strike zones, no infield shifts, extra innings ghost runners, shorter fields, enforcement of the prohibition on the "sticky stuff". They already lowered the mounds in the past; now, they are talking about lowering them more or moving them back. No care for the integrity of the game, only serving to drum up offense for the fans. I am sure Ty Cobb would not be hitting .400 today - especially if they still had the same high mound and none of these other modern inventions.

I did run my hypothesis by Grok, and he agrees that climate change can increase average temperatures in the summer while also lowering day to day variability. So this might explain why the data shows warming, while you remember more 95F & 100F days in the past. A sufficient increase in average temperature should be more than enough to overcome the lessened variance in the future.

Upper 80s on tap for today. Should be the hottest of 2025, so far. The warmest reading observed this year at KPIT is 86F, on June 4th and on April 19th.

Actually, made it up to 95F at Des Moines yesterday, with a record-tying 96F at Waterloo, Iowa!

By hotter, I'm assuming you mean by maximum temperatures. By mean temps, Miami is about 2-3F warmer than Jacksonville. I would chalk that up to JAX having a more continental-influenced climate. While both are on the coast, Miami is at the tip of peninsular Florida. The increased latitude is less significant in the summertime, with insolation probably being about the same at both locations.

Although I think Bristol, Tennesee is probably a better analog. 20 years ago, a regression from 1960 shows very little increase in 90+ days. The same regression run through 2024 now shows an increase of more than 3 weeks of such days. Definitely illustrates the folly of extrapolating from an existing trend without looking at what's going on behind the data. If one had examined the Bristol data closely, they would have noted an increase in the mean high temperature but found the increase in 90+ days somewhat offset by a decrease in internal variability [i.e., day-to-day variance]. So once normal highs climbed a bit more, the number of 90+ days exploded in the last 20 years. 1960-2004 1960-2024

It will probably be like Miami. Looking at a linear regression of 90F+ days, we can see an increase from 31 to 117 such days since 1960. In 1972, there were only 3 days at or above 90F for the entire year! So it went from about one month of 90s to about 1/3 of the calendar year in the 90s.

To clarify, I was referring to the mean high temperature for all of meteorological summer. As an example, a linear regression for Newark shows an increase in mean summer highs from 82.9F to 85.8F between 1960 & 2024. So the mean summer high should reach into the upper 80s over the next couple decades, at which time, July averages would probably be near 90F.

Second 90F reading of the short season to date at O'Hare Airport in Chicago.

Mean summertime high temperatures have risen by 2-3F since 1990. If that trend continues, average summer highs should reach the upper 80s around NYC by 2050, by which time, there should be a marked increase in the number of 90F days [similar to the observed increase in 85F days over the past several decades].