ChescoWx

Both Delaware https://chescowx.com/raw-vs-ncei-delaware/ and New York State https://chescowx.com/raw-vs-ncei-new-york/ are now up and availabe with raw vs anomaly vs NCEI figures charts and trends.

I was asked to compare PHL Airport vs East Nantmeal Twp. In the western philly burbs of Chester County PA for climate since 2004. (see full panel below) Summer afternoons: PHL’s highs run 5.4–6.3°F warmer from June through September. Against the whole county the gap was mainly at night; against East Nantmeal it’s mainly in the daytime. That fits what the siting check found: my fan-aspirated Davis VP2 records cooler highs. Elevation adds to it. Overnight lows: PHL is warmer every month, from 2.8°F in April to 5.1°F in August. Rain and snow: Precipitation: East Nantmeal gets 50.35" a year to PHL’s 45.56". It’s wetter in most months, especially July (5.62" vs 4.66"). Snow: East Nantmeal averages 35.8" a season against 22.7" at PHL, about 58% more. EN had more snow than PHL in all 22 seasons. February shows the biggest difference: 13.4" vs 8.4". Is the temperature gap widening? Yes. It has grown about 0.46°F per decade, mostly in daytime highs (+0.64). PHL warmed about 1.0°F per decade over these 22 years, against 0.55 at East Nantmeal. I will post up Chester County as a whole later. Let me know if any questions. Thanks!

I was asked to compare PHL Airport vs East Nantmeal Twp. In the western philly burbs of Chester County PA for climate since 2004. (see full panel below) Summer afternoons: PHL’s highs run 5.4–6.3°F warmer from June through September. Against the whole county the gap was mainly at night; against East Nantmeal it’s mainly in the daytime. That fits what the siting check found: my fan-aspirated Davis records cool highs. Elevation adds to it. Overnight lows: PHL is warmer every month, from 2.8°F in April to 5.1°F in August. Rain and snow: Precipitation: East Nantmeal gets 50.35" a year to PHL’s 45.56". It’s wetter in most months, especially July (5.62" vs 4.66"). Snow: East Nantmeal averages 35.8" a season against 22.7" at PHL, about 58% more. EN had more snow than PHL in all 22 seasons. February shows the biggest difference: 13.4" vs 8.4". Is the temperature gap widening? Yes. It has grown about 0.46°F per decade, mostly in daytime highs (+0.64). PHL warmed about 1.0°F per decade over these 22 years, against 0.55 at East Nantmeal. I will post up Chester County as a whole later. Let me know if any questions. Thanks!

I was asked to compare PHL Airport vs East Nantmeal Twp. In the western philly burbs of Chester County PA for climate since 2004. (see full panel below) Summer afternoons: PHL’s highs run 5.4–6.3°F warmer from June through September. Against the whole county the gap was mainly at night; against East Nantmeal it’s mainly in the daytime. That fits what the siting check found: my fan-aspirated Davis VP2 records cooler highs. Elevation adds to it. Overnight lows: PHL is warmer every month, from 2.8°F in April to 5.1°F in August. Rain and snow: Precipitation: East Nantmeal gets 50.35" a year to PHL’s 45.56". It’s wetter in most months, especially July (5.62" vs 4.66"). Snow: East Nantmeal averages 35.8" a season against 22.7" at PHL, about 58% more. EN had more snow than PHL in all 22 seasons. February shows the biggest difference: 13.4" vs 8.4". Is the temperature gap widening? Yes. It has grown about 0.46°F per decade, mostly in daytime highs (+0.64). PHL warmed about 1.0°F per decade over these 22 years, against 0.55 at East Nantmeal. I will post up Chester County as a whole later. Let me know if any questions. Thanks!

So far this year through yesterday.

So far this year through yesterday.

Happy Halloween to all of you!! Today we should see highs from upper 50's in ridge locations to the low 60's in valley spots. The NWS has issued a frost advisory for tonight for Eastern Chester County with temperatures just above freezing in valley locations while the ridge tops mainly across Western Chesco stay in the low 40’s. Temperatures will be near normal through Monday but by Tuesday we warm to the upper 60's which is 4 to 8 degrees above normal. It has been a while since our last rain but our next soaking rain looks to arrive Friday with around 1.6" possible according to the ChescoWx model. Of note 160 years ago today back in 1866 the Chester County Area was on the last day of a 3 day storm that left as much as 2.10" of rain at Pocopson. This was the remnants of an unnamed tropical storm which tracked within about 130 miles of the county.

Happy Halloween to all of you!! Today we should see highs from upper 50's in ridge locations to the low 60's in valley spots. The NWS has issued a frost advisory for tonight for Eastern Chester County with temperatures just above freezing in valley locations while the ridge tops mainly across Western Chesco stay in the low 40’s. Temperatures will be near normal through Monday but by Tuesday we warm to the upper 60's which is 4 to 8 degrees above normal. It has been a while since our last rain but our next soaking rain looks to arrive Friday with around 1.6" possible according to the ChescoWx model. Of note 160 years ago today back in 1866 the Chester County Area was on the last day of a 3 day storm that left as much as 2.10" of rain at Pocopson. This was the remnants of an unnamed tropical storm which tracked within about 130 miles of the county.

Of note on this date back in 1946 Phoenixville 1E hit 85 degrees and the county as a whole averaged 83.3 for a high...making it our warmest October 30th since records began in 1890. Nothing like that today but it will be very mild for the end of October with highs from upper 60's in ridge locations to the low 70's in valley spots. This is about 7 degrees above normal with lows tonight in the upper 30's to near 40. By Sunday morning we should see lows in the mid 30's to low 40's, not far from freezing in the colder valleys! Temperatures will be near normal this weekend but by Monday we warm to the upper 60's which is 3 to 8 degrees above normal. It has been a while since our last rain but our next soaking rain looks to arrive Thursday with around 1.2" possible according to the ChescoWx model.

Of note on this date back in 1946 Phoenixville 1E hit 85 degrees and the county as a whole averaged 83.3 for a high...making it our warmest October 30th since records began in 1890. Nothing like that today but it will be very mild for the end of October with highs from upper 60's in ridge locations to the low 70's in valley spots. This is about 7 degrees above normal with lows tonight in the upper 30's to near 40. By Sunday morning we should see lows in the mid 30's to low 40's, not far from freezing in the colder valleys! Temperatures will be near normal this weekend but by Monday we warm to the upper 60's which is 3 to 8 degrees above normal. It has been a while since our last rain but our next soaking rain looks to arrive Thursday with around 1.2" possible according to the ChescoWx model.

"needs" to be "corrected" with estimated homogenization adjustments

The state of Delaware study findings are now up and available at https://chescowx.com/raw-vs-ncei-delaware/

Agree 100% the actual data is clear and consistent across the entire USA not just Yellow Medicine or Chester County.

Since this concerns the impact of Climate Change across the entire USA and not just one individual county - I am happy to share the below study of Actual raw temperature data vs. the NCEI adjusted data for the entire Continental USA. Please find the below combined US 48 state findings (PA and NY are already posted an online). For the full reports and individual state and county findings as they are released over the next 46 days please check out https://chescowx.com/raw-vs-ncei-state-by-state/ THE MAIN STUDY FINDINGS FOR THE CONTINENTAL USA The NWS raw trained observer temperature record shows no significant warming at all in the contiguous 48 states since 1895!! (+0.01 °F per decade). In fact the temperature trend lines across the entire USA are basically flat from 1895 through 2026! However by contrast NCEI's adjusted temperatures show significant warming in the contiguous 48 states since 1895 (+0.18 °F per decade). That difference between the two trend lines is statistically significant. Combining the 48 statewide records of actual readings, each weighted by the state's land area, gives +0.01 °F per decade from 1895 to 2025 (95% range -0.04 to +0.05), about +0.1 °F in total. NCEI's published contiguous-U.S. series gives +0.18 °F per decade (range +0.12 to +0.23), about +2.3 °F in total. Of note NCEI's adjusted temperatures are lower than the actual readings in every single decade from the 1890s through the 1990s. To dig deeper into these continental US wide findings including please check out https://chescowx.com/raw-vs-ncei-co ntiguous-us/

Our 2nd state in the Nationwide Actual Raw vs. NCEI Adjusted Study for New Jersey is now available for review and download. For much more detail including study design, by decade breakdowns, county by county maps and breakdowns for all State Counties that compare actual vs NCEI trends for each NJ county please go to https://chescowx.com/raw-vs-ncei-state-by-state/ The main finding The NWS raw trained observer temperatures show significant warming in New Jersey since 1895 (+0.15 °F per decade). NCEI's adjusted temperatures show about twice as much warming (+0.31 °F per decade). That difference between the two trend lines is statistically significant. Averaging what New Jersey's observers actually recorded, county by county and weighted by county area, gives +0.15 °F per decade from 1895 to 2025 (significant), about +2.0 °F in total. NCEI's published statewide series gives +0.31 °F per decade (significant), about +4.1 °F in total. NCEI's series runs 1.4–1.7 °F below the actual readings in every decade from 1895 through the 1940s; 0.7–1.1 °F below them in the 1950s to 1970s; 0.4–0.6 °F below them in the 1980s and 1990s; within 0.2 °F of them from 2000 on. NCEI's adjusted temperatures are lower than the actual readings in every decade from the 1890s through the 1990s.