ChescoWx

The last 8 week analysis of the temperature at KRDG indicates per the below a possible radiation shield problem for why they are reading so high.

Enjoy today's nice weather with sun and not too humid. Because, much of the upcoming work week looks unsettled weather wise with at least a chance of some showers and thunderstorms almost every day through Thursday. We are near normal for rainfall so far this month and still have a surplus of over 3" for the year to date. Chester County daily records for today: High 106 degrees at Phoenixville (1930)/ Low 48 degrees at Phoenixville (1965) / Rain 3.60" at West Chester (1919)

Enjoy today's nice weather with sun and not too humid. Because, much of the upcoming work week looks unsettled weather wise with at least a chance of some showers and thunderstorms almost every day through Thursday. Chester County daily records for today: High 106 degrees at Phoenixville (1930)/ Low 48 degrees at Phoenixville (1965) / Rain 3.60" at West Chester (1919)

So if there was a "reverse heat island effect" why did NCEI chill Coatesville even more with adjustments? Why did they continue to chill the Doe Run baseline site?? Below are the actual and NCEI altered average temps for each station during the period of record. NCEI chilled Coatesville obs each and every year from 1894 thru 1971. The biggest adjustment by station location was in the 1903-16 timeframe....Charlie mentioned above that no other places in the county had as many 95 plus days during this time. Well actually in the 1910's Sadsburyville had 55 such days - Coatesville 52 days - Phoenixville 46 days. Important to note there was no time of observation bias evidenced at the Coatesville station. Only during the 1910-1921 timeframe were single evening observations recorded at 9pm (1910-1915) and 8pm (1916-1921). Readings were taken three times a day from 1894 thru 1909 at 7am/2pm/9pm. From 1922 to 1945 readings were taken at 8am and 8pm. From 1946 to 1982 readings were observed at 8am

Do you think there is a problem with the KRDG Thermometer? Further north in Berks County - higher elevation yet now consistently warmer than the lowest and warmest somewhat urban location in Chester County - Phoenixville. At this rate KRDG might approach KPHL levels soon.

Hi zenmsav - not rude at all. I suspect you are correct with the self debate LOL! Hopefully folks not interested just ignore this....which most but not are seem to be doing! I do not have average windspeed and humidity for all stations....but I may add those in to my dataset for those that have that data.. Thanks!

Yesterday was on average our warmest day of the year and we were around 6 degrees cooler than normal for July 19th. Today looks to be our 3rd consecutive below normal temp day across most of Chesco. More clouds than sun today but sunny and hotter tomorrow with temps back in the upper 80's. By Tuesday we start to see some pretty unsettled weather with off and on storm chances through the remainder of the upcoming work week. Chester County records for today: High 104 degrees at Phoenixville (1930) / Low 48 degrees at Coatesville (1965) / Rain 3.83" at Coatesville (1981)

Yesterday was on average our warmest day of the year and we were around 6 degrees cooler than normal for July 19th. Today looks to be our 3rd consecutive below normal temp day across most of Chesco. More clouds than sun today but sunny and hotter tomorrow with temps back in the upper 80's. By Tuesday we start to see some pretty unsettled weather with off and on storm chances through the remainder of the upcoming work week. Chester County records for today: High 104 degrees at Phoenixville (1930) / Low 48 degrees at Coatesville (1965) / Rain 3.83" at Coatesville (1981)

Actually it's 25 sad little stations to best analyze the climate of Chester County PA. The true defining question to ask is.....can a man get pregnant?

So what is the "required adjustment" for these reverse heat island impacts when they moved to the more suburban sites?? Should the adjustment... at let's say Coatesville be to adjust the temperature up or down?? What years should be decreased and which ones increased??

Charlie so where was the Philadelphia obs taken in the above data you are using? It looks to me like the Philadelphia data from the 1890's thru 1930's was taken near Roxborough correct??

Coatesville and West Chester "more urban" than Philly in 1936? It was just warmer west of Philly in 1936 before the UHI contamination of Philly was underway.

By popular request....More updated charts based on the data refinements last week identified by Charlie. As you can see below with the actual raw data (blue) over the last 130 years (at least here in Chester County PA) there is almost a flat trend to our annual average temperatures by decade. Of course if we apply the NCEI adjustments we now see the warming trend. I will also attach the NCEI adjustments by decade. Which after 11 decades of consistent cooling adjustments...we now have post observation warming adjustments being applied.

Hey Frank sounds like another of the Ghost Stations found right here in PA

A refresher for those considering joining the dust bowl heatwave deniers. Showing how Chester County like most of the USA experienced summers hotter than we have experienced since...even in our current warming cycle of climate change. https://arcfieldweather.com/blog/2024/7/3/the-deadly-heat-wave-of-july-1936in-the-middle-of-one-of-the-hottest-summers-on-recordin-the-middle-of-one-of-the-hottest-decades-ever

There continues to be an alarming rise in dust bowl heatwave deniers....they continue to attempt to use altered adjusted data to chill that historical heat. While reviewing all of the post hoc data adjustments details for the long term Chester County PA stations I found plenty of missing data points for both West Chester and Phoenixville.. I have included their raw unaltered data for the below summertime average temperature historical review of the years these deniers focus on most 1930's thru 1950's. Below is a comparison of the actual raw data along with the significant cooling adjustment following NCEI adjustments. Coatesville individual post hoc site NCEI altered average summertime temperatures are in red. Chester County PA NCEI county wide altered average temperature following NCEI adjustments are in purple. Of note, as I dove into the handwritten observations for Coatesville there appears to be no need for time of observation adjustments for Coatesville, During the time frame of all of these significant cooling adjustments the time of observation for Coatesville was taken by the observer at the following times. 1930 thru 1942 at both 8am and 8pm; from 1942-1945 it was 8pm. After 1945 it was taken at 8am.

Most spots across Chester County over the last 7 days have received between 1" to over 3" of rain. Here in East Nantmeal we have received 3.07" of rain since last Thursday. Spots across Southern Chester County have been generally on the lower side of these amounts with more to the North across the county. A nice stretch of weather through the weekend is on the way. Relatively low humidity and temps not far from normal to slightly below. Chester County daily records for today: High 100 degrees at West Chester (1988) / Low 50.6 at Nottingham (2014) / Rainfall 2.75" at Phoenixville (2019)

Most spots across Chester County over the last 7 days have received between 1" to over 3" of rain. Here in East Nantmeal we have received 3.07" of rain since last Thursday. Spots across Southern Chester County have been generally on the lower side of these amounts with more to the North across the county. A nice stretch of weather through the weekend is on the way. Relatively low humidity and temps not far from normal to slightly below. Chester County daily records for today: High 100 degrees at West Chester (1988) / Low 50.6 at Nottingham (2014) / Rainfall 2.75" at Phoenixville (2019)

Widespread 90's again yesterday. In fact yesterday was the first time I have recorded back to back 90 degree days in East Nantmeal since July19-21st in 2020. Another shot at 90 today...but with a strong front sweeping in from the west by late PM or early evening it may keep some folks just below 90 degrees. Strong storms are again possible this evening and then a great stretch of weather with temperatures even a little below normal for Thursday and Friday. Of note on average tomorrow the 18th is the warmest day of the year...for those who love winter average temps begin a slow fall that will continue until the coldest day of the year on January 21st. Daily Chester County records for today: High 101 degrees at West Chester (1988) / Low 42 degrees at Devault (1954)/ Rain 2.61" at Phoenixville (2018)

Widespread 90's again yesterday. In fact yesterday was the first time I have recorded back to back 90 degree days in East Nantmeal since July19-21st in 2020. Another shot at 90 today...but with a strong front sweeping in from the west by late PM or early evening it may keep some folks just below 90 degrees. Strong storms are again possible this evening and then a great stretch of weather with temperatures even a little below normal for Thursday and Friday. Of note on average tomorrow the 18th is the warmest day of the year...for those who love winter average temps begin a slow fall that will continue until the coldest day of the year on January 21st. Daily Chester County records for today: High 101 degrees at West Chester (1988) / Low 42 degrees at Devault (1954)/ Rain 2.61" at Phoenixville (2018)

Below is the average summertime (June thru August) average temperatures by decade for Chester County since the 1890's. The hottest complete decades were back in the 1930's and 1940's. We are only 3 years in to the 2020's but so far we are tied for 2nd warmest decade but plenty of years left to work on this decade.

Here in East Nantmeal we exceeded 90 degrees for just the 2nd time this year (90.5) with the 2nd hottest day of the year behind only the 91.9 on June 22nd. Other area high temps yesterday included Brandwine Airport (95.0) Chester Springs (94.9 ) and Warwick Twp. (94.0). Today will be even hotter with widespread mid to upper 90's. Shower chances increase later today and again tomorrow as a cold front moves through later Wednesday. It will turn much more comfortable by Thursday with temperatures closer to average for what is normally our warmest week of the year. Chester County Records for today: High 100 degrees at Coatesville (1900) / Low 46 degrees also at Coatesville (1929) / Rain 2.66" at Kennett Square (1911)

Here in East Nantmeal we exceeded 90 degrees for just the 2nd time this year (90.5) with the 2nd hottest day of the year behind only the 91.9 on June 22nd. Other area high temps yesterday included Brandwine Airport (95.0) Chester Springs (94.9 ) and Warwick Twp. (94.0). Today will be even hotter with widespread mid to upper 90's. Shower chances increase later today and again tomorrow as a cold front moves through later Wednesday. It will turn much more comfortable by Thursday with temperatures closer to average for what is normally our warmest week of the year. Chester County Records for today: High 100 degrees at Coatesville (1900) / Low 46 degrees also at Coatesville (1929) / Rain 2.66" at Kennett Square (1911)

Most spots except the higher elevations hit 90 degrees yesterday more of the same today and then even hotter Monday and Tuesday with mid to upper 90's especially in lower spots. Cold front slices thru by Wednesday night with temps close to normal but most importantly lower humidity by late week. Chester County records for today: High 102 degrees in Phoenixville (1954) / Low 50 degrees at Devault (1960)/ Rain 4.00" at West Grove (1975)

Most spots except the higher elevations hit 90 degrees yesterday more of the same today and then even hotter Monday and Tuesday with mid to upper 90's especially in lower spots. Cold front slices thru by Wednesday night with temps close to normal but most importantly lower humidity by late week. Chester County records for today: High 102 degrees in Phoenixville (1954) / Low 50 degrees at Devault (1960)/ Rain 4.00" at West Grove (1975)