ChescoWx

Charlie, no need for an apology to anyone as I only analyze the actual NWS data. But since you say I never give you anything beyond stations....well below please find all the deep details for the NWS COOP and MADIS stations in our Chester County PA dataset. Included in the below chart - I also updated your above chart with the correct data inventory dates for all available complete years of record. Data provided below for all historical and currently available NWS COOP/MADIS stations includes station map coordinates, full years of data observations by station and elevation above sea level for each station of record. Some interesting historical and going forward geographic data and station reporting splits. There are 704 complete years of all station historical data available through December 31, 2023. 368 years of total data or 52% of the years have been observed at elevations below 407 FT ASL (relative lower spots) 336 years of total data or 48% of the years have been observed at elevations over 440 FT ASL (relative higher spots) Pre-1990 we have 451 years of historical total station data 256 or 57% of those earlier observations were taken at relative lower elevations 195 or 43% of those earlier observations were taken at relatively higher elevations Going forward we will have a split of 8 stations located below 407 FT ASL and 8 stations above 440 FT ASL That said we only had 55 years of observations at the relatively highest levels above 600 feet prior to 1990. These ongoing observations will include 5 stations (31%) between 620 ft and 685 ft / 5 stations (31%) between 407 ft and 465 ft and 6 stations (38%) reporting data between 105 ft. and 348 ft.

Most spots except the highest stations exceeded 90 degrees...as both West Grove and East Nantmeal reached 89.6 degrees. The warmest station high was the 95.1 at West Chester.However, whether it's 89.6 or 95 degrees....one thing is for sure - It's oppressively hot and humid! The next couple days will again see 90's in most spots. Rain chances do increase starting tomorrow and looks to last through Friday. After tomorrow most spots will fall into the 80's for high temps. We should clear out for the weekend. Chester County Records for today: The all-time recorded PA high based on records was recorded today and tomorrow in Phoenixville at 111 degrees in 1936. This reading has been called into question as both West Chester and Coatesville "only" reported 103 degrees that same day. Highly unlikely there was an 8 degree difference on that day. The record low was 44 degrees also at Phoenixville in 1972. Record rain was the 5.82" at Phoenixville in 1935.

Most spots except the highest stations exceeded 90 degrees...as both West Grove and East Nantmeal reached 89.6 degrees. The warmest station high was the 95.1 at West Chester.However, whether it's 89.6 or 95 degrees....one thing is for sure - It's oppressively hot and humid! The next couple days will again see 90's in most spots. Rain chances do increase starting tomorrow and looks to last through Friday. After tomorrow most spots will fall into the 80's for high temps. We should clear out for the weekend. Chester County Records for today: The all-time recorded PA high based on records was recorded today and tomorrow in Phoenixville at 111 degrees in 1936. This reading has been called into question as both West Chester and Coatesville "only" reported 103 degrees that same day. Highly unlikely there was an 8 degree difference on that day. The record low was 44 degrees also at Phoenixville in 1972. Record rain was the 5.82" at Phoenixville in 1935.

So with the new corrected actual COOP data for Chester County PA that eliminated any ghost/estimate data from the observation database we found the following. From 1893 thru 1927 no change in the data For 86 consecutive years from 1928 thru 2013 each year has now cooled with the elimination of the ghost/estimate data See the actual average annual temperature variance (red with ghosted/estimated data included and blue with the revised clean actual data from 1893 thru 2023) Clearly the elimination of these ghosted averages has further flattened the warming trend lines.....

Well I finished scrubbing and updating the data. The data looks much better!! I only had to totally delete the Chadds Ford and Honey Brook data. There were many years of good COOP data remaining at all other sites - so only had to delete years at the front or end of the station records. All in all it looks like it may end up with a bit cooler overall look regarding Chester County average temperatures through the years, Having the Phoenixville data ghosted into the Devault data and some of the other estimated data that looks to have skewed us a bit warm may make the difference. Will run some analysis later. Thx

I am having a blast with this!! Fortunately a bit slow at work so I am crunching away on where ghost data is and is not. Some stations have ghost data for decades and then over to actual for decades and then back to ghost! It will be fascinating to see how it all shakes out. I hope to get everything tied up later today or tomorrow. Wish me luck! Thanks again for the heads up!!

Nope - just an excellent VP station with fan aspiration for better accuracy. Plus I am the highest elevation spot reporting, The closest to my elevation in the County is West Grove MADIS 650 ft ASL they have reported a high of 89.5 today with my East Nantmeal station at 685 feet reporting a high of 89.6 so far today. See my station temperature health check for today - all good!

Below is an example of the newest Ghost Station in the Coatesville and Chester County data set. I am working up a list of all real vs ghosted data (and correct dates) to appropriately adjust the Chesco database. I actually have found 2 Ghost Stations in Coatesville one back in the 1940's-1950's and this new one since 2016. Both of these stations are actually NWS Coop precipitation sites that have had post hoc approximate temperatures added to their observations. Below is Coatesville 1E vs. KMQS Airport near same elevation and within 2 NM of the Airport. The month is August 2022. The Ghost Coatesville site reported 11 days over 90 degrees while KMQS and Glenmoore only reported 2 such days. The ghost data increased the average temperature by 1.2 degrees vs KMQS in just that month.

A few spots picked up some showers last evening including 0.14" at Chester Springs...most folks however saw little or no rain. Most spots except the higher locations like Atglen, West Grove and East Nantmeal exceeded 90 degrees. More 90's and high humidity likely through Wednesday....before shower chances increase with the impact of the remnants of Beryl by late week. Chester County records for today: High 101 degrees at Phoenixville (1936) / Low 49 degrees at Coatesville (1954) / Rain 3.44" at Phoenixville (1964)

A few spots picked up some showers last evening including 0.14" at Chester Springs...most folks however saw little or no rain. Most spots except the higher locations like Atglen, West Grove and East Nantmeal exceeded 90 degrees. More 90's and high humidity likely through Wednesday....before shower chances increase with the impact of the remnants of Beryl by late week. Chester County records for today: High 101 degrees at Phoenixville (1936) / Low 49 degrees at Coatesville (1954) / Rain 3.44" at Phoenixville (1964)

As I continue to dig deeper into the analysis for my area of Chester County PA. So far I have found the following additional ghost station data adjustments, these are in addition to Glenmoore, Honey Brook, Chadds Ford, and West Grove (pre 1963) Devault reported ghosted Phoenixville PA readings starting from January 1893 thru June 1, 1951. Devault recorded their own actual observations from June 1951 through January 31, 1988 Devault resumed reporting ghost data from Phoenixville on February 1, 1988 through April 3, 2005 Downingtown PA 2000 thru 2003 all ghosted data looks to be aligned to the Chadds Ford Ghosted Data.... Morgantown PA began ghosting data on February 2, 1986 following actual data from 1951 thru January 1986

Some info on ghost stations - those E's that Charlie mentioned may indeed be these non-existent stations. “They are physically gone—but still report data—like magic,” said Lt. Col. John Shewchuk, a certified consulting meteorologist.“NOAA fabricates temperature data for more than 30 percent of the 1,218 USHCN reporting stations that no longer exist.” He calls them “ghost” stations. Of interest they are still finding more of these stations. In fact one that has been identified is West Chester which last reported real data back in 2017. Do we have more stations we have identified that we can send on over? Mr. Shewchuck said USHCN stations reached a maximum of 1,218 stations in 1957, but after 1990 the number of active stations began declining due to aging equipment and personnel retirements. NOAA still records data from these ghost stations by taking the temperature readings from surrounding stations, and recording their average for the ghost station, followed by an “E,” for estimate. The addition of the ghost station data means NOAA’s “monthly and yearly reports are not representative of reality,” said Anthony Watts, a meteorologist and senior fellow for environment and climate at the Heartland Institute. https://amac.us/blog/health-and-wellness/hidden-behind-climate-policies-data-from-nonexistent-temperature-stations/

Thanks to Charlie for the great heads up!! While we need to do a bit more analysis.... but see below for an analysis of the IEM data set vs. actual obs. These estimates at least in this one month are running warmer than the actual obs by over 1 degree in August 2005. It is starting to look like some of these IEM stations and their data might be what some in the climate world have coined "ghost stations" where older stations are either replaced with these estimates - like we clearly see in near 20 years of the Glenmoore Data. If this is true I will of course strip out these "ghost" stations and only use real data. While the ghost data is similar between these ghost stations....there is some subtle differences. The blue is where the actual real obs are the same as the estimate for Glenmoore - with the yellow differences from the Glenmoore ghost data. It will be interesting to see the impact of stripping out these non-actual data points.

With all the above up there said I am not sure exactly what is going on and will go back and do some further analytics. I just love these kind of puzzles!!. I am after all a recovering accountant/finance guy! I am sure it will become clear if NCEI simply copies certain stations over - as I found in the past with old Devault data. But the big question comes if they are using averaged data from 1 station or some sort of derived estimate and then paste it across additional stations that would of course impact any calculations done....thus weighting more heavily on estimated data or adjusted data - if in fact this data is actually used as part of NCEI's adjustment to the actual or calculation of their adjusted averages. Should be fun!

Plenty of inconsistencies in the above Glenmoore PA comments. First we are told that there was not any temperature data at all for this station and only rain. Later...sorry no actually it looks like the temperature sensor was installed in 2009. But as we see below we have the evidence that the observer has been reporting temperatures to the NWS consistently at least as far back as nearly 20 years! (see below August 2005 handwritten submitted obs). So Then we see that the NCEI Historical Observing Metadata Repository site has begun to erase the fact that data was observed at least that far back.... but has not yet apparently updated for 2009 (still listing temp obs). NCEI true to their word is well on the way to revising the past data as we can see they have "cleaned up" August 2005 below with their updated computer output eliminating the Glenmoore handwritten obs. Call me stunned NCEI adjusting or eliminating data after the fact - I never would have thought such a thing LOL!! Now we need to ask well where is the analysis to support the deletion of this station data? Well they do mention above these supposed reliability concerns....sounds fair but where is the analysis against a control station or 2 to show how unreliable this station supposedly is? Is that station running "statistically" higher or lower than surrounding "valid" stations to invalidate the readings? Well, no details have been provided of that analysis.... just we feel like there are "reliability concerns" and it is not NWS approved. A little analysis and comparison to the closest surrounding stations does not show any issues with the data. In fact in the final year that Glenmoore/Coatesville and East Nantmeal (2007) all reported they were within 0.1 degree of each other in average temperature. East Nantmeal is within 2 nautical miles of the Glenmoore COOP observer within 60 feet of elevation. So even though not NWS approved that data sure passes the statistical p-value to validate and remains extremely consistent with the current Glenmoore MADIS station and of course East Nantmeal.

All spots across the County exceeded the 90 degree mark with the oh so close exception of East Nantmeal where we could "only" reach 89.9 degrees!. The next coolest spot was West Grove at 90.9. Some of the hotter spots included Chester Springs 95 degrees and. KOQN Brandywine Airport also 95. The hot temps looks to continue for the next few days before we drop back into the 80's by Wednesday. Along with the temp drop will come increasing shower chances by Tuesday night. Each day from Wednesday thru Saturday will feature a chance at some showers. Chester County records for today: High 103 degrees at Phoenixville (2010)/ Low was 47 degrees at West Chester (2001) / Rain 2.23" at Coatesville (1907)

All spots across the County exceeded the 90 degree mark with the oh so close exception of East Nantmeal where we could "only" reach 89.9 degrees!. The next coolest spot was West Grove at 90.9. Some of the hotter spots included Chester Springs 95 degrees and. KOQN Brandywine Airport also 95. The hot temps looks to continue for the next few days before we drop back into the 80's by Wednesday. Along with the temp drop will come increasing shower chances by Tuesday night. Each day from Wednesday thru Saturday will feature a chance at some showers. Chester County records for today: High 103 degrees at Phoenixville (2010)/ Low was 47 degrees at West Chester (2001) / Rain 2.23" at Coatesville (1907)

Even though it has an E flag on the Data Calendar below there actually is submitted NWS Coop forms (see below) that show the actual observations taken. The dataset I am using for the analysis matches the below official coop data form and does not use the estimated figures on the data calendar. You can see the differences below. Not sure why they would put estimates in when we have actual data?

Hey Charlie looks like quite a bit of missing data under the IEM sites. To your point they list Glenmoore as having no temperature data for March 2009 (see below) but there were temperature obs taken per obs sheet. They do correctly record the precipitation however. These reading align with my dataset for Glenmoore for that month. The metadata sourced from the Penn State Climate site also shows no temps and only rain data....strange!

The only issue I found during my QC was that they had simply mirrored Devault data with Phoenixville from 1893 thru 1951. Devault did not begin daily temperature obs till 1951....so I deleted all of those years for Devault. Otherwise the data is consistent but with clear obs variations between the various stations see below for example.

Most locations exceeded 90 degrees yesterday with the only exceptions being the higher spots like West Grove (88.2) and East Nantmeal (88.5). The heat advisory will continue through tomorrow with temps again in the 90's at most spots. There is a chance of some scattered storms today with a better chance by Tuesday and through mid-week. While year to date we are still over 2" above normal rainfall the last 2 months we are running about 2.5" below normal. Chester County records for today: High 103 degrees at Phoenixville (2010) / Low 45 degrees at Morgantown/Elverson (1979)/ Rain 4.15" at Chadds Ford (1989)

Most locations exceeded 90 degrees yesterday with the only exceptions being the higher spots like West Grove (88.2) and East Nantmeal (88.5). The heat advisory will continue through tomorrow with temps again in the 90's at most spots. There is a chance of some scattered storms today with a better chance by Tuesday and through mid-week. While year to date we are still over 2" above normal rainfall the last 2 months we are running about 2.5" below normal. Chester County records for today: High 103 degrees at Phoenixville (2010) / Low 45 degrees at Morgantown/Elverson (1979)/ Rain 4.15" at Chadds Ford (1989)

No worries Don....I have made a few of those myself! Even though we may disagree on some of these big issues I still enjoy your posts!! take care!!

And no matter how many machine produced non-Chester County obs you put forth.....we know it is not real or factual data. The facts are not supportive....I feel your pain!!

Fortunately we have plenty more stations that say.....sorry Charlie!!