TheClimateChanger

Ok, well, it looks like eastern Pennsylvania did a bit better in terms of cold. The 44F at Mount Pocono was only the 33rd warmest minimum for the month of August (since 1902). In western Pennsylvania, whenever there is a cold snap these days, it's accompanied by thick stratocumulus from the Great Lakes preventing radiational cooling from occurring. But, on the same token, Mount Pocono has not been below 40F in the month of August since 1992. From 1902-1992 - a total of 92 years, but for which only data exists for only 86 years - there were 46 years in which the temperature dropped below 40F in the month of August. In other words, a temperature that used to be observed more frequently than every other year has not occurred in over three decades.

As I noted here, it was at or below freezing throughout western Pennsylvania outside of the heat island areas in August 1982. It was even 38F in suburban Washington, D.C. at Dulles International Airport. What was the low temperature in Cashtown in August 1982? Are you saying the ASOS temperatures are incorrect or unreliable? And, if so, why would they just start being wrong in recent years?

I don't know what this matters. The only first-order stations to reach below 50F were Bradford (47F) and Mount Pocono (44F). The minimum was exactly 50 at Johnstown-Cambria County and Altoona. These stations have been in the same location for decades. Sheltered valley locations can get quite a bit colder than mountain locations.

At Bradford, the temperature used to drop to at or below freezing about once every five or six years in the month of August. It has not dropped below 40F since 2014.

At Bradford Regional Airport, the monthly minimum of 47F was just one shy of the warmest of record for the month of August behind 1980's low of 48F. Records date to 1957. It was also the fourth warmest minimum for any month. Also of note, July 2023's minimum of 49F tied 2020 for the warmest of record.

The monthly minimum temperature for August at DuBois - Jefferson County Regional Airport was 51F, which ties 1980 for warmest minimum temperature. Records date to 1962. Additionally, it was the 7th warmest monthly low temperature for any month. All six warmer minima occurred in July. Of note, this past July's minimum temperature of 53F was the second highest of record, behind 54F from 2020.

Also, of note, Miami's low of 83F was just one shy of the all-time record warmest minimum temperature there. This was an unusual 12:24 a.m. reading, so just at the very beginning of the calendar day. The rest of the day was 84F+. What is interesting is Wikipedia indicates that the all-time record warm low of 84F occurred twice - on August 4, 1993 & September 7, 1897. You can tell this was authored several years ago. In the new normal, an 84F low occurs pretty much every single year, often multiple times in a year. Since this article was written, a low of 84F has been observed nine times at Miami (August 5, 2017, September 8, 2017, July 14, 2019, June 25, 2020, June 27, 2020, June 29, 2020, July 31, 2020, September 3, 2020, and July 20, 2023).

The temperature at Naples dropped to 86F yesterday, which still was the warmest minimum on record at the airport. Using the expanded records for Naples area, which extend back to 1942, we can find one more alleged instance of an 86F low temperature, which is said to have occurred on August 17, 1943 (see below).

Upper 80s in western Pennsylvania looks about right, too. That's what the forecast is calling for Sunday. You never see the GFS spit out 110F for Pittsburgh.

Not sure if it will hold, but in the wake of Idalia, Naples Municipal Airport (APF) appears to have had a low of only 87F this morning. Short period of record, but looking back on the records, which date to 2003, this appears to be the warmest low over those 21 years. The daily mean of 90F, should it hold, is also the highest in the 21 year period. Naples, Naples Municipal Airport (weather.gov)

I think the high of 85 would have been on the 28th, but observed at 7 am on the 29th and ascribed to the date on which it was read. But even so, yes, the max thermometer at that station was clearly reading too high. Probably being exposed to some sunlight at some point. Looking at other observations around the region, there was indeed a large diurnal range. But it was more on the order of high 60s / low 70s for afternoon highs, not 80.

Even Reddit is complaining about the heat already.

The airport is at 2100 feet. The town is more like 1400-1500 feet, so it was probably a few degrees warmer in town. At the airport elevation, no, I don't believe it would be practical to grow tomatoes outside of a greenhouse in a natural climate. In the native climate, the frost-free period seems to be too short. You might get a few tomatoes, but I doubt much yield. Today, it would probably be much more feasible since summertime frosts no longer occur.

Ok, so I did some further research. Here was the article in the WaPo from 8/30/1982, discussing the cold snap: A Cold Snap Replaces Usual August Steambath - The Washington Post Note the record low of 38F in suburban Washington, D.C. at Dulles International Airport. A location more noted for its hot, subtropical climate and lack of snow, saw temperatures dipping into the 30s. As you can see, most people absolutely loved that weather: Of course, they did. Who doesn't like a crisp morning, followed by a warm, sunny afternoon in the 70s? The article does speculate that there could be crop damage from the midwest where temperatures dropped into the 20s. But if we look at the actual data, we see 1982 corn yield came in way above trend. The poor yield years (1983, 1988, 1991, 1993, 1995, 2002, 2011, and 2012) were from heat and drought (except 1993 may have been heat and flooding). The best yield years occur in cold, wet summers (1992, 2004, & 2009). The point being a little frost in August is probably not a big deal. The still high sun angle and short nights probably limited any frost to a couple hours near sunrise, with rapid melting by 7-7:30 am, preventing any significant damage. I mean perhaps yields would have been slightly higher without the cold snap. But it's clear from the data that heat and drought are a much bigger threat to agriculture than a quick, early frost.

I didn't know Bradford, Pennsylvania was an important agricultural region.

Anyways, I'm allowed to be upset about the loss of a natural climate. Regardless of whether the elimination of occasional late summer frosts and freezes were advantageous to agriculture. Just look at Bradford, Pennsylvania. Used to be one of the coldest spots in the country. August freezes in 1965, 1968, 1972, 1976, 1982, and 1986. None since 1986. It hasn't even been below 40F in the month of August since 2014, and the last time below 38F was in 2004. I mean look, it's barely dropped below 50F this month. This type of a change has to have a drastic impact on the local ecosystem. Just because it hasn't impacted the U.P. to the same degree yet, don't think you won't escape these changes. Bradford, Pennsylvania is in one of the most remote parts of the eastern U.S., surrounded by the Allegheny National Forest.

The point is not silly or stupid. Sure, the 1982 cold snap was a record-breaker. Now, we're lucky to see a day or two below 50F, but it used to dip into the 30s in August regularly. It's that dramatic of a change. We likely won't see 1982 conditions for two months.

It seems the latest sensor is a bit more favorable for warmth. PIT has gone from consistently the coldest spot other than DUJ at 1800' (maybe tied with HLG) to the warmest spot, except for maybe MGW. Makes sense given the heat island at the airport, plus the construction going on. Also went from 1-1.5F cooler than AGC in recent months, to 0.5F warmer so far this month. Although, I feel some of that is attributable to a cooler sensor installation at AGC. I think mid 90s are a definite possibility if we can get enough of the warmth aloft to overspread our area, unlike the heat wave last week.

Funny that frost in the UP is now seen as a big deal in late August. We used to have hard freezes in Ohio in late August just a few decades ago.

Some other low temperatures reported on this date in 1982 include 27F at Canfield, Ohio; 27F at Millport, Ohio (near Lisbon, Ohio); 30F at Warren, Ohio; 31F at Mercer; 31F at Clarion; 34F at Waynesburg; and 34F at Uniontown. This was widespread frost and freezing conditions outside of the immediate heat island.

For a little weather history, on this date in 1982, the region was in the throes of an impressive late August cold snap. The official low temperature was 39F at PIT. However, typically colder locations saw freezing conditions. Low temperatures included 26F at Bradford; 28F at Slippery Rock, 29F at Washington; 32F at New Castle; 32F at Youngstown, Ohio; and 34F at DuBois. Bradford Slippery Rock Washington, PA New Castle Youngstown, Ohio DuBois

It is sure looking like we are going to see our hottest temperatures of the season in September. It seems like the first half of September every year features temperatures rivaling or exceeding the summertime maxima these days.

Now this is an actual cold summer. On this date 41 years ago, the temperature dropped to 38 at Washington-Dulles Airport. Widespread frost, and even areas of freezing conditions, throughout the eastern US. https://www.washingtonpost.com/archive/local/1982/08/30/a-cold-snap-replaces-usual-august-steambath/8ae62318-f533-4734-8ef0-2f9d4a99edc5/

On this date in 1982, record low of 38 at Dulles. Frost and even freezing conditions at many places in the eastern U.S. https://www.washingtonpost.com/archive/local/1982/08/30/a-cold-snap-replaces-usual-august-steambath/8ae62318-f533-4734-8ef0-2f9d4a99edc5/

Looks like the Houston record may be short-lived.