ChescoWx

At 8am is not a big deal as we have shown before....minor to no issues.....6pm for 3 years....no big deal

Max sun and then the 24-hour Davis VP2 Fan Aspiration Radiation Shield kicks in for maximum accuracy

Here in East Nantmeal we picked up 0.17" of needed rain overnight. We see sun return again today with a few degrees cooler than the last several days. Temps should stay in the upper 80's with maybe a few lower spots touching 90 degrees. Rain chances increase by tomorrow PM through Saturday morning - fingers crossed! The local farmers and lawns could surely use a bit more rain. While we are still 1.70" above normal with rain and melted snow so far this year....we are 4.03" below normal through yesterday here in East Nantmeal. Chester County records for today: High 106 degrees at Phoenixville (1936) / Low 45 degrees at Coatesville way back in 1898/ Rain 4.53" at Phoenixville (2019)

Here in East Nantmeal we picked up 0.17" of needed rain overnight. We see sun return again today with a few degrees cooler than the last several days. Temps should stay in the upper 80's with maybe a few lower spots touching 90 degrees. Rain chances increase by tomorrow PM through Saturday morning - fingers crossed! The local farmers and lawns could surely use a bit more rain. While we are still 1.70" above normal with rain and melted snow so far this year....we are 4.03" below normal through yesterday here in East Nantmeal. Chester County records for today: High 106 degrees at Phoenixville (1936) / Low 45 degrees at Coatesville way back in 1898/ Rain 4.53" at Phoenixville (2019)

Below are all 5 sites used and their dates. Overall siting looks pretty consistent over a very short distance. It looks like the "warmest" relative observing site very well might have been the one near the steel mill plant from 1917 to 1930. Overall all of this Coatesville data observation moves clearly did not have much of an impressive material impact on these stations and more importantly on the overall averages for Chester County overall.

Reading's thermometer has been an issue for while....see latest gladstone - red x is not good

You did not answer my question.....

As you should know Charlie one station does not a trend make....So why did Phoenixville's nights chill even more than Coatesville when we compare that same time frame without a station movement there?? Maybe it was just a little chillier in the 1948 to 1960 period??

75.6 for the warm AM low in East Nantmeal. After today we should get a brief break from 90 degree temps till the weekend. Rain chances start to ramp up this afternoon and especially tonight. We are all hoping for some beneficial rains. By early next week the heat returns....it sounds like July!! Stay cool! Chester County records for today: High 111 degrees at Phoenixville but 105 degrees at West Chester (1936) / Low 42 degrees at Devault (1954) / Rain 4.35" at West Chester (1931)

75.6 for the warm AM low in East Nantmeal. After today we should get a brief break from 90 degree temps till the weekend. Rain chances start to ramp up this afternoon and especially tonight. We are all hoping for some beneficial rains. By early next week the heat returns....it sounds like July!! Stay cool! Chester County records for today: High 111 degrees at Phoenixville but 105 degrees at West Chester (1936) / Low 42 degrees at Devault (1954) / Rain 4.35" at West Chester (1931)

Close only counts in checkers....Sounds like a certain pot calling the kettle black....LOL!!!!

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!