TheClimateChanger

Not to be overly pedantic but official records did not move to PIT until September 15, 1952, at which time the airport was called The Greater Pittsburgh Airport. I realize some sources incorrectly show data back to 1949 as belonging to PIT, but this is incorrect. The airport didn't even open until 1952. You can see the actual records in the NCEI records vault (see September 1952 below). So 1949-50, 1950-51 and 1951-52, which all appear in the table above, were actually observed at AGC not PIT.

Not good news with all of the drought. Looks like these multi-year Ninas may be becoming more frequent due to climate change. https://www.washington.edu/news/2022/10/03/study-suggests-la-nina-winters-could-keep-on-coming/

It looks 2011-2012 might be a decent analog as well, which was a multi-year ENSO?

Do you guys think 1988-1989 is a good analog for the upcoming winter? I noticed Joe Bastardi indicated that this was the coldest start to October since 1988, although I know he can sometimes take liberties with data. Regardless, I thought that was interesting since I also recently read that the Mississippi River at Memphis recently went below the prior record low set in 1988. So both years had widespread drought across the CONUS, a chilly October, and a similar ENSO state at this point - although 1988-1989 went on to become a strong La Nina whereas I believe most forecasts for this winter are weak to moderate La Nina.

Only 17.77% of the country not in some drought designation level, which is the lowest amount since they've been producing the drought monitors (which go all the way back to 1/4/2000).

Yesterday's drought monitor (valid 10/18) shows the least amount of the U.S. not in some drought designation (D0-D4) since they've been producing the drought monitor (back to 1/4/2000). Only 17.77% of the U.S. was not in one of the drought categories. The previous record was 18.22% the prior week (10/11/2022). Third place is 7/17/2012, when only 19.24% was not designated in a drought category.

Well, officially. But almost everybody had way more than that across the region.

Where is this storm track in January? Only ever happens in the fall when it’s still too warm for snow - like Superstorm Sandy, although that one happened later in the month and gave the mountains a nice pasting.

Two days above 90F was the 5th most on record, and it was the first June ever to reach or exceed 90F.

Well - it's all relative. Bradford is about as non-urban and highly elevated as you get, and is was the 2nd hottest summer (of 64 years) there. Of course, it's like 10 degrees cooler than Harrisburg - but it's still warming every bit as fast, if not faster.

Pretty balanced overall. Highs were 3.4F above normal, and lows were 3.7F above normal. 14 days were at or above 90F, 8.5 more than normal. And 10 more than have been recorded at Pittsburgh International this entire year. 000CXUS51 KCTP 010634CLMMDTCLIMATE REPORT NATIONAL WEATHER SERVICE STATE COLLEGE PA234 AM EDT THU SEP 01 2022......................................THE HARRISBURG PA CLIMATE SUMMARY FOR THE MONTH OF AUGUST 2022...CLIMATE NORMAL PERIOD 1991 TO 2020CLIMATE RECORD PERIOD 1888 TO 2022WEATHER OBSERVED NORMAL DEPART LAST YEAR'S VALUE DATE(S) VALUE FROM VALUE DATE(S) NORMAL ................................................................TEMPERATURE (F)RECORD HIGH 104 08/07/1918 08/06/1918 LOW 45 08/31/1976 HIGHEST 95 08/09 96 08/12 08/04 LOWEST 59 08/13 60 08/03 08/05 AVG. MAXIMUM 88.1 84.7 3.4 86.8 AVG. MINIMUM 69.5 65.8 3.7 69.9 MEAN 78.8 75.2 3.6 78.3 DAYS MAX >= 90 14 5.5 8.5 12 DAYS MAX <= 32 0 0.0 0.0 0 DAYS MIN <= 32 0 0.0 0.0 0 DAYS MIN <= 0 0 0.0 0.0 0 PRECIPITATION (INCHES)RECORD MAXIMUM 10.67 1933 MINIMUM 0.53 1995 TOTALS 1.14 3.77 -2.63 5.88 DAILY AVG. 0.04 0.12 -0.08 0.19 DAYS >= .01 8 10.0 -2.0 14 DAYS >= .10 3 6.2 -3.2 9 DAYS >= .50 1 2.5 -1.5 4 DAYS >= 1.00 0 1.0 -1.0 2 GREATEST 24 HR. TOTAL 0.54 07/31 TO 08/01 1.85 08/17 TO 08/18SNOWFALL (INCHES)RECORDS TOTAL 0.0 MM TOTALS 0.0 0.0 0.0 0.0 SINCE 7/1 0.0 0.0 0.0 MM SNOWDEPTH AVG. 0 0 DAYS >= 1.0 0 0.0 0.0 0 GREATEST SNOW DEPTH 0 0 MM 24 HR TOTAL MM MM DEGREE DAYSHEATING TOTAL 0 1 -1 0 SINCE 7/1 0 0 0 MM COOLING TOTAL 435 319 116 421 SINCE 1/1 1206 1021 185 MM ................................................................WIND (MPH)AVERAGE WIND SPEED 6.1 HIGHEST WIND SPEED/DIRECTION 39/300 DATE 08/04 HIGHEST GUST SPEED/DIRECTION 50/300 DATE 08/04 SKY COVERPOSSIBLE SUNSHINE (PERCENT) MM AVERAGE SKY COVER 0.50 NUMBER OF DAYS FAIR 8 NUMBER OF DAYS PC 18 NUMBER OF DAYS CLOUDY 5 AVERAGE RH (PERCENT) 61 WEATHER CONDITIONS. NUMBER OF DAYS WITH THUNDERSTORM 10 MIXED PRECIP 0 HEAVY RAIN 3 RAIN 3 LIGHT RAIN 12 FREEZING RAIN 0 LT FREEZING RAIN 0 HAIL 0 HEAVY SNOW 0 SNOW 0 LIGHT SNOW 0 SLEET 0 FOG 2 FOG W/VIS <= 1/4 MILE 0 HAZE 4 - INDICATES NEGATIVE NUMBERS.R INDICATES RECORD WAS SET OR TIED.MM INDICATES DATA IS MISSING.T INDICATES TRACE AMOUNT.$$

Another scorching summer for central parts of the Keystone state. With one day left, Harrisburg is tied for 5th hottest summer (out of 135 years), Williamsport is in 9th place (out of 128 years), Altoona is in 12th place (out of 75 years), and Bradford is tied for 2nd place (out of 64 years). In all cases (except for Bradford, where this summer is tied with 2020 for second place), it is cooler than each of the last two summers. Below are the numbers and placement. In brackets, I indicated what the ranking would have been prior to 2016. There have been several hot summers just in the past 7 years - with 2016, 2018, 2020, and 2021 showing up in the top ten at many sites, and 2019 also appearing at Harrisburg. This also marks the 5th consecutive summer with at least one of the following 4 sites observing a top ten warmest summer. Harrisburg, PA (T-5th place) [Prior to 2016: T-2nd place] Williamsport, PA (9th place) [Prior to 2016: 7th place] Bradford, PA (T-2nd place) [Prior to 2016: 1st place] Altoona, PA (T-12th place) [Prior to 2016: T-8th place]

We've really lucked out on the 90+ front locally. Most of the region has seen way more 90+ days (as in double digits). Pittsburgh has only had 4 days, but Morgantown has had 15, Youngstown 10, Canton/Akron, OH 16, Cleveland 13. Even Erie has had 5, and DuBois (1800') 4. And I should note the 4 days is the official numbers from PIT Airport. YMMV, as AGC has had 9 90+ days. And I'm sure if there were still weather observations taken in the city, it would easily be in the double digits.

Do you think this is a start of a new trend? I didn't realize global warming would cause lapse rates to decrease until Joe Bastardi posted on July 16th of this year that the lapse rates aren't changing. But I think lapse rates are decreasing because that would explain why rural, extremely low population density locations, in the mountains show as much, or more warming, than big urban areas at lower elevations (like Bradford, Pennsylvania - shown below, with the ten warmest summers since 1957). That would be the opposite of what would be predicted by the theory of the urban heat island effect. So if lapse rates are, in fact, decreasing, will that lead to greater atmospheric stability in the summertime and less convective rainfall? I think what may happen is the rain will become less frequent, but when it does rain, it will fall heavier from the increase in atmospheric water vapor. Which I think is consistent with what the models show, by and large. If this is true, then hopefully state and local governments will prepare for more frequent droughts, and even possible fire weather conditions, in the warm season, even while total precipitation is steady or increasing.

Just to illustrate. Here is the U.S. annual mean temperature trend: The early years are fairly well mixed, but there's definitely some bias below the trend line up until about 1920. However, recent years are almost exclusively above trend - in some cases, way above trend. Since 1998, only 4 years have been colder than the trend, with one additional year (2010) almost smack dab on the trend line. So it looks to me like the warming is accelerating at an alarming pace - not to sound too alarmist! Trend would probably also steepen if they included data from the 1870s and 1880s. While limited most of the available data suggests this period was significantly colder than the turn of the 20th century.

Interesting... crazy to see my hometown has warmed over 3.5F since 1961, but not shocking. One thing I'll say is these are based on linear regressions, which are also used to estimate the trend. However - and maybe it's just me - but I've noticed these temperature trend linear regressions tend to have the majority of early years lying below them and the majority of the recent years lying above them. If the change were truly linear, you would expect a mix of years above and below throughout the period of examination. What this suggests to me is the trend is actually increasing - that is, as more and more years go by, we should expect to see the slope of the trend lines increase over time. Not a good sign.

There was like a very impressive 8-day heat wave in July 1936, but the rest of the month was a "summer of yesteryear" with comfortable temperatures and low humidity. It's like a weeklong heat wave that gets blown way out of proportion. I wonder why Bastardi never uses his population weighted metrics on that summer? It looks like the core of the heat was in places where nobody lives.

Was 1936 really the hottest summer in U.S. history? Looking at the data, I'm not sure it was... it looks mostly to be an artifact of the algorithm. Hagerstown, Maryland was 3.8 degrees below modern norms in July 1936, yet Washington County, Maryland shows up as warmer than normal for that month due to extreme smoothing likely as a result of bad figures elsewhere. One county south at Martinsburg, West Virginia, it was supposedly 2.8 degrees above modern norms. This is obviously ridiculous... there are days that month where the Martinsburg co-op are 10+ degrees warmer than the Hagerstown site? Morgantown came in cooler than normal with a mean temperature of 72.8F, yet somehow Monongalia County is shown as above normal with a mean of 72.7F. How could the county - mostly rural, with high mountain ridges in the east - have a mean only 0.1F lower than the observations from the city, which undoubtedly would have been the warmest spot in the county? So much bad data from that era, yet it gets repeated ad nauseum. The low temperatures at many spots were truly at summer of yesteryear levels in July 1936 with many nights in the 40s and 50s. No need for A/C with that radiational cooling. Look at Brookville, PA (not even high elevation - 1100') - the monthly mean low temperature was below 50F that month. 4th coldest minimum temperatures at Morgantown, WV in the station thread. 6th coldest in the Wheeling, West Virginia station thread. Allegany and Cattaraugus Counties in New York have minimum temperatures 2nd and 3rd lowest in the entire data set. More importantly, it's supposedly a tiny fraction warmer than last summer, but those numbers don't include the Great Lake water temperatures, which cover a large expanse of the U.S. If you include those lake surface temperatures, I think several recent years would easily surpass it. Just look at the lake surface temperatures at Buffalo from that year... Frozen over until May 16th, only year later was 1971. Hasn't been freezing water temperatures in the month of May since 1996. https://www.weather.gov/buf/LakeErieMay. Water temperatures stayed well below seasonal averages all through June: https://www.weather.gov/buf/LakeErieJune Water temperatures opened July much cooler than normal, briefly spiked to near record levels with the major heat episode, then cooled back down. The 70 degree reading on July 31, 1936 hasn't been matched since the chilly summer of 2009. It's only been cooler on that date on three years (1956, 1962 and the volcanic summer of 1992): https://www.weather.gov/buf/LakeErieJuly

I just remember growing up and years like 1988 & 1995 were considered the gold standard for summertime heat with media driven to a frenzy about it being a once-in-a-lifetime deadly heat wave. It's crazy to me to see so many recent summers post similar, or warmer, mean temperatures than those years.

Only Toledo, earlier this year. But none of those cities reach 100+ with any degree of frequency. I think you're right about part of the cause - its simply more humid today than it was during some of the past heatwaves. But I do think some of it just comes down to more reliable equipment and better techniques for measuring the temperature. Even 1988... do a little research on the HO-83 that was in common use at the time at these first order climate sites... it was hot, no doubt, but there's a plethora of scientific studies showing a considerable warm bias related to that device on Tmax, especially on sunny days with light winds. It was so bad NOAA/NWS had to replace it in the mid 1990s. I think it's going to continue to be harder to see 100+ days with modern shielded, fan-aspirated equipment properly sited on the ground... in the 30s-50s, it was very common for city and airport records to be collected on building rooftops, which have since been shown to have a considerable warm bias. I think, to some extent, this effect was known at the time, but it was just deemed more convenient to house all of the equipment together and the anemometer needed to be located way above ground for reliability.

It seems like the Midwest has seen more than its fair share of heat in recent years, no? Not sure how much hotter y'all want it to get. Top ten hottest summer lists in Ohio and Michigan are dominated by recent summers. Lansing, Michigan: 2005, 2010, 2012, 2016, 2020, 2021, and 2022 (so far) in top ten. Saginaw, Michigan: 2010, 2012, 2020, and 2021 in top ten. Flint, Michigan: 2010 & 2016 in top ten. Detroit, Michigan: 2005, 2010, 2011, 2012, 2016, 2018, and 2021 in top ten. Alpena, Michigan: 2005, 2012, 2016, 2018, and 2021 in top ten. Traverse City, Michigan: 2005, 2012, 2016, 2018, 2020, and 2021 in top ten. Toledo, Ohio: 2002, 2005, 2010, 2020, 2021 and 2022 (so far) in top ten. Mansfield, Ohio: 2016, 2018, 2020 and 2021 in top ten. Cleveland, Ohio: 2005, 2010, 2012, 2016, and 2018 in top ten. Akron, Ohio: 2016, 2018, 2020, 2021, and 2022 (so far) in top ten.

Well, April 1875 was like the 19th century opposite of "Morch" of 2012. But, yeah, it could have been worse.

Anyways, even reading three degrees too high, I'm glad they didn't remove the record high on the 4th. It's probably still more reliable than the rooftop records from various buildings downtown for the first 65 years of the station thread. Or the 1870s method of taking the temperature from a sheltered window. The Weather Bureau actually continued to take records downtown until at least 1978... from 1953-1978, it averaged about 2.6F higher than PIT airport. And from 1936-1951, it was about 1.9F warmer than AGC. From 1999-2021, AGC averaged 0.6F warmer than PIT, suggesting the difference was pretty robust from the two periods. Although I suspect some of the 1800s records are probably 3-4F too warm compared to modern readings. https://www.weather.gov/pbz/stationhistory

Not sure, but it would appear the sensor or fan malfunctioned or failed in the last handful of days of August and was corrected around September 11. I looked at the hourly observations on the 9th and PIT had humidity levels generally between 87%-90%. You'd expect with such heavy rain humidity would be closer to 97-100%. I'm not really sure how it happens, but I noticed the humidity will often appear lower when a station is reporting too high, which is somewhat weird because the humidity is supposed to be calculated separately and the dewpoint determined from the temperature and humidity. So you would think it would just result in the dewpoint also registering too high. Perhaps a fan issue, where the air parcel was being heated by the heating elements in the ASOS without proper ventilation which would leave the dewpoint unaffected, and thus result in the humidity registering too low?

Not really much difference between the two sites. Since 1999, July has averaged 0.24" drier at AGC and 0.4F warmer on the mean. Maxima have averaged just 0.1F warmer, and minima 0.7F warmer. With that said, the difference between the two sites this July is within the variance of prior years. Although there have been only 3 years in which AGC was more than 1.0F warmer in the month of July, and all three of them AGC was substantially drier than PIT (1999, 2000 & 2005 average: 2.79" drier). This suggests at least a portion of the difference of the difference was due to drier soil moisture conditions. In the table below, red means AGC was warmer and blue means PIT was warmer. Note that the mean difference looks like it should be 0.5F, but that's due to rounding (the values to two decimal places are 73.85F and 73.43F). What's interesting is how much of a difference that 0.42F difference would make to the record warmest Julys. NWS PBZ has a list of 12 Julys in which the mean was at or above 77.0F - all but one was from the old downtown site. The lone exception is July 2020, at 77.3F (or 8th place on the list). But if AGC were still the official source of records, July 2020 would move up to 4th place (78.2F) and 1999, 2011, and 2012 would all place in the top ten.