ChescoWx

More info on my winter forecast - In the identified analog years below only 2 of the 10 winter seasons resulted in above average snow seasons...hence why my winter forecast has an 80% likelihood of below normal snow. Below are the analog seasons and the snowfall: 1902/03 - 25.8" / 1913/14 - 54.1" / 1927/28 - 38.5" / 1931/32 - 9.0" / 1935/36 - 34.0" / 1975/76 - 19.0" / 1985/86 - 26.3" / 2001/02 - 11.1" / 2005/06 - 31.4" and 2016/17 - 24.0 Only snowstorms in these analog years >10" were: January 29, 1928 - 20.0"/ February 12, 2006 - 18.0" / March 2, 1914 - 12.0" / February 14, 1914 - 10.4" / February 24, 1914 - 10.4" and February 17, 1903 - 10.0"

Hey guys, Below is my latest climate recap article for the local paper and includes my pass at a winter forecast - let me know what you think and enjoy! Hello again from Paul at the East Nantmeal PA Weather Station (www.chescowx.com). Be sure to follow me on twitter at chescopawxman where I am tweeting daily climate reports, forecast updates and weather and drone photos of our beautiful Township. I hope all of you are staying well and safe! Since the last New Sweetwater Reporter, we have moved from summer into mid-fall. Let’s quickly recap our weather here in the Township. July was a warm month finishing with an average temperature of 77.0 degrees which is 5.0 degrees above normal See the below summer months summary that details our 1st “heat wave” in East Nantmeal Township in the last 2 years. Rainfall was 5.52” or 0.77” above normal. August, finished only slightly above average with a temperature of 73.5 or 1.3 degrees above normal. However, rainfall wise thanks to the impacts of Hurricane Isaias which drenched the township with a new record daily rainfall of 5.83” we finished August with 8.38” of rain or 4.01” above normal. Below is a summer recap for East Nantmeal Township with some of the facts and figures of this past summer season. Summer (June thru August) climate summary for East Nantmeal Township PA. For the summer months (Jun-Jul-Aug) here in East Nantmeal we finished with an average temperature of 73.7 This is the 17th warmest summer since 1894 Of note the 5 hottest summers were all before 1955 (warmest being the summer of 1900 at 75.8 degrees!) Coldest reading - 44.1 on June 1st Warmest reading - 92.0 on July 19th Only our 2nd heat wave (3 straight 90+ days) in the last 8 years!! We have had only 10 heat waves in the last 18 years those being on July 1- 3, 2018 /July 5-7, 2012 / July 21-24, 2011 / July 4-7, 2010 / July 18-20, 2008 / June 7-10, 2008 / August 1-3, 2006 / August 12-14, 2005 / June 24-26, 2003 / August 1-5, 2002 5 days exceeded 90 degrees this summer this represented our most here in the Township in 9 years since the 11 such days back in 2011 A bit surprising for the many warming climate believers…only 4 of the 17 warmest summers have occurred since 1988 and the top 5 all before 1956 and 13 of the 17 warmest summers also occurred prior to 1956 Top 5 warmest summers were (1900 - 75.8 / 1901 - 75.0 / 1944- 75.0/ 1955 - 75.0 and 1943 -74.9) Precipitation wise we received 17.63" of rain - average summer months rainfall is 13.16" (+4.49" above avg.) so a good year for the many farmer in our beautiful township This was the 15th wettest summer on record with the wettest occurring just 2 summers ago in 2018 when 26.29" of rain drenched East Nantmeal Township Finally, a fascinating comparison (see below) that helps highlight the increasing heat island impact that we consistently see at the Philadelphia International Airport (PHL) compared to the more rural airport observation locations in suburban Eastern PA of Coatesville, Reading and Pottstown where we are noting a clear decline in 90+ days – some notable facts out of this data. In just the last 2 years PHL airport has recording 67 days above 90 degrees (the other 3 sites combined over the last 4 years only 61 days!) With 17 years of records for these locations - Note that over the last 8 years a significant drop in the number of 90+ days at the rural sites compared to the prior 9 years However, at the Philadelphia airport - the frequency of 90+ days continues to increase at a fast pace....this disparity between the PHL heat island and suburbia is likely to continue as the heat island impact shows little sign of abating – so as mentioned before take the mentions of heat waves on the local news as a unique feature of the heat island locales in the close in Philadelphia suburbs and not representative of where we live in East Nantmeal Township. The dawn of the month that marks the start of the Autumn season delivered our 1st below normal month in the last 3 months since the back to back below normal months of April and May. September finished with an average reading of 64.4 or (0.6 degrees below normal) – it was also a very dry month with only 2.22” of rain falling…well below our normal 4.74” that fall in East Nantmeal. We did record 2 daily record low temperatures during the month with the 41.1 on the 19th and the 40.2 on the 21st. October was a somewhat normal month with a slightly above average temperature of 55.2 (+1.3) and near normal rain of 4.34” (+0.16 to avg.). We did record our 1st freezing temperature on Halloween morning at 32 degrees this ended our growing season at 174 days since our last freeze on May 10th. These 174 days were 14 days less than our normal growing season for our farmer of 188 days. November has been incredibly warm with even 5 straight days between the 6th and 10th exceeding the 70-degree mark. As I sit here on the 21st of the month I believe we have a good chance to finish in the top-5 warmest Novembers on record! So, what does this mean for our upcoming winter season? Well it is indeed time for my annual winter forecast for Western Chester County PA and specifically for our backyards here in beautiful East Nantmeal. As some may remember my winter forecast for last winter was just as bad as all the professional meteorologist who also forecast a cold and snowy winter. This year I have taken a different approach. I have focused on what we call analog seasons – looking for similar fall months in relation to normal along with an eye to the anticipated La Niña pattern that many find a strong predictor of future weather. With that said I have identified based on our fall patterns 10 of these analog years with what I think will be a somewhat weaker La Niña pattern compared to many of the more moderate professional forecasts I have seen. My 10 analog seasons are in reverse time order 2016/17 – 2005/06 – 2001/02 – 1985/86 – 1975/76 – 1935/36 – 1931/32 – 1927/28 – 1913/14 and 1902/03 With all that in mind below is my winter forecast for Western Chester County PA and specifically for East Nantmeal Township with departures vs. average · November 2020 – Avg. Temp 49.7 (+5.8) w/ no snow (-1.3”) - December 2020 – Avg, Temp at 35.0 (+0.4) w/ Snow of 4.3” (-0.4”) · January 2021 – Avg. Temp at 32.5 (+2.5) w/ Snow of 6.7” (-4.0”) · February 2021 – Avg. Temp at 34.0 (+1.5) w/ Snow of 9.5” (-2.3”) · March 2021 – Avg. Temp at 41.4 (+0.9) w/ Snow of 6.1” (normal avg.) · April 2021 – Avg. Temp 51.4 (+0.1) w/ Snow of 0.3” (-0.7”) To summarize - every month of the winter season is forecast to average warmer than normal temperatures, with all but March averaging below normal snowfall. Total 2020/21 snowfall forecast is 26.9” or 9” below our normal seasonal snow average of 35.9” Now, regarding potential major snowstorms based on the analog years I have identified we have a: · 70% chance of at least one storm at over 6” of snow · 40% chance of . 1 storm exceeding 10” of snow · 20% chance of a storm over 15” · 10% chance of a storm over 20” So, while not likely to be a cold or snowy winter - keep those snow blowers handy and enjoy the holiday season with your family and friends and please stay safe and healthy! All the best - Paul “Some are weather-wise, some are otherwise” Ben Franklin

25.3 for the low this AM - coldest since the 22.4 reading on March 1st

Put almost as much faith in their forecast as I do my upcoming forecast for the winter.....not an exact science as we all know!

The high today of only 38.0 in Western Chester County PA marks our 1st sub 40 high since March 6th (39.3) - our current temperature of 28.2 marks our 1st sub 30 degree reading this cold weather season and 1st sub 30 reading since way back on March 1st (22.4)

Only made it down to 32.0 exactly - only 2nd time all season and tied with the 32.0 on Halloween. Normally 9 such days by today...also we are already at below normal snowfall for the season....sign of the season to come??

So putting the final touches on my "fearless" winter forecast for Western Chester County PA - due next week. My 10 analog seasons I am going to use not in rank order are 1902/1913/1927/1931/1935/1975/1985/2001/2005 and 2016 - anyone want to venture a guess as to why those years?

Little light shower of snow, sleet and rain here in East Nantmeal Twp. with a temp of 46.4

WXSIM text forecast for East Nantmeal, initialized at 9:00 AM Nov 16, 2020 _______________________________________________________________________________ Today: Mostly sunny in the morning, becoming sunny in the afternoon. High 49. Wind west around 7 mph, gusting to 19 mph. Tonight: Clear in the evening, becoming mostly clear after midnight, with areas of light frost likely. Low 30. Wind west around 4 mph. Tuesday: Partly cloudy in the morning, becoming partly to mostly cloudy in the afternoon. High 45. Wind west around 6 mph, gusting to 16 mph, in the morning, becoming 9 mph, gusting to 18 mph, in the afternoon. Tuesday night: Fair to partly cloudy in the evening, becoming clear after midnight, with areas of light frost likely. Low 31. Wind chill ranging from 25 to 35. Wind west-northwest around 9 mph, gusting to 18 mph. Wednesday: Sunny. High 40. Wind northwest around 8 mph, gusting to 19 mph. Wednesday night: Clear, with moderate to heavy frost. Low 27. Wind north-northwest around 2 mph in the evening, becoming southwest after midnight. Thursday: Mostly sunny in the morning, becoming partly cloudy in the afternoon. High 48. Wind southwest around 5 mph, gusting to 15 mph, in the morning, becoming 10 mph, gusting to 18 mph, in the afternoon. Thursday night: Partly cloudy in the evening, becoming fair to partly cloudy after midnight, with scattered light frost possible. Low 33. Wind southwest around 7 mph. Friday: Mostly sunny in the morning, becoming sunny in the afternoon. Relatively mild. High 58. Wind southwest around 6 mph. Friday night: Clear, with light to moderate frost. Low 32. Wind west-southwest around 3 mph. Saturday: Sunny. Relatively mild. High 56. Wind west-northwest around 2 mph in the morning, becoming west-southwest in the afternoon. Saturday night: Clear, with areas of light frost likely. Low 32. Wind south around 2 mph. Sunday: Partly to mostly sunny in the morning, becoming partly to mostly cloudy in the afternoon. Relatively mild. High 58. Wind south around 7 mph, gusting to 17 mph. Sunday night: Mostly cloudy to cloudy in the evening, becoming cloudy after midnight. Low 42. Wind south around 5 mph. Monday: Dense overcast. Rain likely. High 48. Wind south-southwest around 2 mph. Chance of precipitation 70 percent. Precipitation mostly between a quarter and half an inch. Monday night: Dense overcast. Relatively mild. Low 45. Wind south-southwest near calm. Tuesday: Dense overcast. High 50. Wind south-southwest around 2 mph. Tuesday night: Dense overcast. Relatively mild. Low 46. Wind south-southwest near calm.

Powering flickering as the squall line is on our doorstep - temp now falling after just reaching high for the day of 62.8

WXSIM forecasts 6 of the next 9 nights with below freezing temps- we have only had one such day so far this season in Western Chesco >650ft. Through today we normally have already had 9 such days WXSIM text forecast for East Nantmeal, initialized at 5:00 PM Nov 14, 2020 _______________________________________________________________________________ Tonight: Fair to partly cloudy in the evening, becoming partly cloudy after midnight, with scattered light frost possible. Low 36. Wind north around 2 mph in the evening, becoming east-southeast after midnight. Sunday: Mostly cloudy in the morning, becoming cloudy in the afternoon. A chance of rain in the afternoon. Breezy. High 52. Wind south-southeast around 9 mph, gusting to 18 mph, in the morning, becoming 15 mph, gusting to 20 mph, in the afternoon. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch. Sunday night: Mostly cloudy in the evening, becoming fair after midnight. Rain likely. Breezy. Low 37. Wind west around 12 mph, gusting to 20 mph. Chance of precipitation 70 percent. Precipitation mostly around half an inch. Monday: Sunny. High 48. Wind west around 11 mph, gusting to 22 mph. Monday night: Clear in the evening, becoming fair after midnight. Low 32. Wind west around 7 mph. Tuesday: Partly cloudy in the morning, becoming partly to mostly sunny in the afternoon. High 45. Wind west around 9 mph, gusting to 19 mph. Tuesday night: Fair to partly cloudy in the evening, becoming clear after midnight, with areas of light frost likely. Low 31. Wind chill ranging from 26 to 35. Wind west around 9 mph, gusting to 20 mph, in the evening, becoming

A beautiful mid-fall day across the area with highs ranging from 55.8 down the shore in Sea Isle City NJ and 52.8 here in East Nantmeal Twp. almost spot on to our average high for the day of 53.0

another 0.03" of rain today with storm total up to 1.19" temp has also continued to fall steadily now down to 49.7 YTD up to 47.02" or +4.36" above normal thru yesterday Wxsim has our 1st couple of days with temps remaining in the 30's next Wed and Thursday with our brief chill shot

1.16" of rain total with 0.26" since midnight - temps down 5 degrees over last 30 min - current 56.4

Let's look at the seasonal snowfall in the years that we had at least 5 days over degrees in November - avg. Chester County Snowfall is 35.6" 1896/97 = 43.6" 1903/04 = 41.1" 1902/03 = 25.8" 1913/14 = 54.1" 1931/32 = 9.0" 1938/39 = 29.0" 1975/76 = 19.0" 1990/91 = 23.8" 2020/21 = ??

I went back into the database (1894 to Present) to see what the 70 degree climatology looks like for November in Chester County PA 71 years of 128 (55%) on record have seen days over 70 degrees The most 70 degree days in November in rank order 1975 - 8 / 1990 - 6/ 1896 - 7 / 1931 - 7 / 1902 - 5 / 1903 - 5 / 1913 - 5 / 1938 - 5/ 2020 - 5 The most consecutive 70 degree days in November were the 8 straight days between Nov 2nd and 9th in 1975 - this year is the 4th time we have had 5 straight 70+ days in November The longest stretch between November's without a 70 degree was in this past decade between 2009 and 2014 we experienced no days over 70 degrees in November Of Note in 1950 we actually had back to back days exceeding 80 degrees in November

Our 3rd straight record high temp in Chester County PA

Our 3rd straight record daily high in East Nantmeal Twp in Chester County PA. Today's 74.1 beating the old mark of 73 set way back in 1931...temps begin trending downward tomorrow with some rain arriving

Another record high today in NW Chester County PA today while we have eclipsed the old relative elevation record (71.0 in 1994)..... we will not like yesterday - when we set an all-time record high of 76.2 be exceeding the current all-time record which is 78 set today back in 1975

As I prepare for my annual winter forecast due into the local Sweetwater Reported on the 23rd for Western Chester County PA - I have been looking at some past facts and figures from the County to see if they may offer a glimpse into the upcoming winter season. Since we are starting off the month with well above normal temps (although looking ahead while we will finish with above normal temps it will not be top 10 warm IMHO)....I thought I would look at the top 10 warmest November months in our data set since 1894 and see what if any impact that has on the upcoming winter season regarding snowfall. Keeping in mind that average snowfall here in Chester County is 35.9" - below are the top 10 warmest November months and their corresponding following winter snow seasons