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