Pittsburgh/Western PA Summer 2022 Discussion

[Ahoff]

20 minutes ago, Gordo74 said:

Just barely in there.  Meanwhile early not too far away either.  Really that looks like average I'd guess.

[TimB]

Incredibly, PIT’s high today will be pretty close to the last two days.

[Ahoff]

1 hour ago, TimB said:

Incredibly, PIT’s high today will be pretty close to the last two days.

No real rain, which was a surprise.  I expected all day rain.  Just weird weather.

[TimB]

6 minutes ago, Ahoff said:

No real rain, which was a surprise.  I expected all day rain.  Just weird weather.

Speak for yourself, lol.

[Ahoff]

6 minutes ago, TimB said:

Speak for yourself, lol.

I am.  Area wide there was no widespread rain, at least yet.

[TimB]

16 minutes ago, Ahoff said:

I am.  Area wide there was no widespread rain, at least yet.

Definitely very localized. AGC saw over an inch earlier and I’m pretty sure I’ve seen over an inch imby in the last couple hours, but PIT is still sitting at a T for the day.

[Ahoff]

Looks like, right now there is nearly perfect weather for the end of this week into the weekend.  Low humidity, sunny and highs on either side of 80, and some lows maybe in the 50s.  After this extended period of humid weather, I can't wait.

[KPITSnow]

NWS showing low to mid 70’s for highs and low I mid 50’s for lows e d of this week. I am so ready 

[KPITSnow]

If you have somewhere you can get a good view north right now there a a pretty good lightning show with the line of storms up over Erie…which is amazing since it’s 100 miles away.

[PghPirates27]

I saw it. Pretty crazy I had to check the radar and was surprised to see how far away it was.

[TheClimateChanger]

Maybe I have too much time on my hands, but I went through every first-order climate site in PIT's CWA and all surrounding offices (CLE, ILN, BUF, RLX, CTP, and LWX) and only a few locations have received 4 or fewer 90+ days. Most lower elevations sites have 2-4x that amount, with up to 5-7x that amount in the Coastal Plain and a couple of other particularly low elevation sites. Except for MFD and HLG, there's BUF next to Lake Erie and several high elevation sites with DUJ at 1800' and EKN, BFD, BKW and JST all above 2000'. Even AGC (which was the official site from 7/1/1935-9/16/1952) is at 9 days, which honestly seems more in line with most observations.

PIT 4

DUJ 4

MFD 4

BUF 4

HLG 3

EKN 3

BFD 2

BKW 1

JST 0

[TimB]

9 minutes ago, TheClimateChanger said:

Maybe I have too much time on my hands, but I went through every first-order climate site in PIT's CWA and all surrounding offices (CLE, ILN, BUF, RLX, CTP, and LWX) and only a few locations have received 4 or fewer 90+ days. Most lower elevations sites have 2-4x that amount, with up to 5-7x that amount in the Coastal Plain and a couple of other particularly low elevation sites. Except for MFD and HLG, there's BUF next to Lake Erie and several high elevation sites with DUJ at 1800' and EKN, BFD, BKW and JST all above 2000'. Even AGC (which was the official site from 7/1/1935-9/16/1952) is at 9 days, which honestly seems more in line with most observations.

PIT 4

DUJ 4

MFD 4

BUF 4

HLG 3

EKN 3

BFD 2

BKW 1

JST 0

It’d be a lot easier to say “something isn’t right” if it weren’t for that pesky 3 at HLG, where the elevation, latitude, and climo are remarkably similar to PIT’s. The location of AGC is a bit more firmly within the UHI area, which would conceivably lead to a few more 90 degree days in what has been an above normal temperature summer. My question (and maybe yours) isn’t whether or not PIT’s data is bad, but whether PIT is representative of the greater Pittsburgh area, and it very well may not be. But to change that now would render the past 70 years of data moot and not able to be compared to data going forward. And 1952-2022 is unfortunately a pretty critical part of the climate record.

[Ahoff]

Looks like an extended cool period coming.

[TimB]

6 minutes ago, Ahoff said:

Looks like an extended cool period coming.

I’m ready. Hope we’re not sacrificing fall to get this pattern in mid-August, but we’re in desperate need of some 70s/50s highs and lows.

[Ahoff]

1 hour ago, TimB said:

I’m ready. Hope we’re not sacrificing fall to get this pattern in mid-August, but we’re in desperate need of some 70s/50s highs and lows.

Yeah, I do hope we don't reset to summer come September.

[TimB]

What an ugly day. So much cloud cover so far in August. I’m ready for the sunshine starting tomorrow. Have to remind myself it’s already cooler and less humid than it’s been the past several days, but looking out the window it doesn’t look any different.

[Ahoff]

So much for the start of beautiful weather.  Raining.

Good thing we had a great first half of summer, because this second half sucks.

[TimB]

 

3 hours ago, Ahoff said:

So much for the start of beautiful weather.  Raining.

Good thing we had a great first half of summer, because this second half sucks.

But can you draw up a much better late afternoon in late summer than this? A fair amount of sun, a light breeze, falling dew points and temperatures just a hair below normal. Only thing that would make it better is if it were the weekend, and at least the first half of the weekend looks to be a carbon copy of what we have right now.

[Ahoff]

15 hours ago, TimB said:

 

But can you draw up a much better late afternoon in late summer than this? A fair amount of sun, a light breeze, falling dew points and temperatures just a hair below normal. Only thing that would make it better is if it were the weekend, and at least the first half of the weekend looks to be a carbon copy of what we have right now.

Yeah, no rain, lol.  That was the one hiccup.  Today looks absolutely perfect.

[TheClimateChanger]

On 8/9/2022 at 3:36 PM, TimB said:

It’d be a lot easier to say “something isn’t right” if it weren’t for that pesky 3 at HLG, where the elevation, latitude, and climo are remarkably similar to PIT’s. The location of AGC is a bit more firmly within the UHI area, which would conceivably lead to a few more 90 degree days in what has been an above normal temperature summer. My question (and maybe yours) isn’t whether or not PIT’s data is bad, but whether PIT is representative of the greater Pittsburgh area, and it very well may not be. But to change that now would render the past 70 years of data moot and not able to be compared to data going forward. And 1952-2022 is unfortunately a pretty critical part of the climate record.

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.

[TimB]

22 minutes ago, TheClimateChanger said:

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.

An excellent analysis, thank you. Have you ever analyzed September 2018? I’ve lamented before that I think something is wrong with PIT’s data (which includes a record high on 9/4). 
 

PIT:

 

AGC:

 

PIT ran 3.15 degrees above AGC for the first 10 days of the month, then promptly was on par with or slightly below AGC from the 11th on. The part that is particularly suspect to me is the 4-8(!) degree discrepancies on the 8th through the 10th (the duration of the remnants of Gordon), which seems nearly impossible during an area wide steady rain under completely overcast skies.

[TheClimateChanger]

1 hour ago, TimB said:

An excellent analysis, thank you. Have you ever analyzed September 2018? I’ve lamented before that I think something is wrong with PIT’s data (which includes a record high on 9/4). 
 

PIT:

 

AGC:

 

PIT ran 3.15 degrees above AGC for the first 10 days of the month, then promptly was on par with or slightly below AGC from the 11th on. The part that is particularly suspect to me is the 4-8(!) degree discrepancies on the 8th through the 10th (the duration of the remnants of Gordon), which seems nearly impossible during an area wide steady rain under completely overcast skies.

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?

[TheClimateChanger]

5 minutes ago, TheClimateChanger said:

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?

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

[TimB]

1 minute ago, TheClimateChanger said:

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. 

https://www.weather.gov/pbz/stationhistory

And that’s also a good point. If we’re going to keep the absolute garbage records from the 1800s in the record books, maybe I shouldn’t worry about the sanctity of a record that was likely broken by a bad ASOS sensor four years ago.

One other interesting note: PIT recorded a high of 60 on 9/9/18 with the allegedly bad sensor while the high at AGC was 57. The record low max for that date is 58, and a high of 57 or less would have not only been a record low max, but the earliest such high temperature in the season on record.

[TimB]

15 minutes ago, TheClimateChanger said:

Although I suspect some of the 1800s records are probably 3-4F too warm compared to modern readings.

So the infamous record low max of 25 on 4/18/1875 might have really been 21 or 22? 

[TheClimateChanger]

 

29 minutes ago, TimB said:

So the infamous record low max of 25 on 4/18/1875 might have really been 21 or 22? 

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

 

[KPITSnow]

This has honestly been one of the more comfortable august stretches I can remember and it so far doesn't look like high 80's and 90's are on the horizon.

[Ahoff]

9 hours ago, KPITSnow said:

This has honestly been one of the more comfortable august stretches I can remember and it so far doesn't look like high 80's and 90's are on the horizon.

Looks like a few lower to possibly mid 80s for a couple days starting tomorrow.  But no big heat.  I just hope there isn't a turn around to heat in September.

[Gordo74]

Quite a storm system this morning north of the city.

[north pgh]

Yes lot's of lightning and thunder. 1.62 inches of rain in my gauge since midnight last night. I love storms when you can just lie in bed and relax.