September hit the ground running with the remnants of Hurricane Ida making for a soggy start on the 1st.
The 4.95 inches of rain officially recorded that day was the 12th rainiest day on record in the 152-year precipitation database and a date record.
After Ida, chilly conditions set in for several days and that’s the way the month ended as well. The middle was mild and more than balanced out the cool start and finish.
“September was the third consecutive month that began cool the first several days, but ended warmer than normal,” said Berks weather historian Jeffrey R. Stoudt. “Oppressive heat was rare or absent as no day reached 90 for the second consecutive September.”
August was so warm that it ended tied for hottest August on record. About three of four Septembers have at least one 90-degree day, Stoudt said.
The last 90 in 2021 recorded was Aug. 27. That was similar to 2020 when the last 90 was recorded Aug. 26. The previous two years each had a small number of 90s in September.
The top September in Berks for 90s was in 1961 and that month is also the warmest September on record by a fairly wide margin. There is a sprinkling of 90s in the first 10 days of October in the record period.
Of rain and normals
“Heavy rain from tropical rainstorm Ida at the very beginning of the month was easily the key event,” Stoudt added.
Most locations in Berks received 4 to 7 inches of rain, said Stoudt, who oversees numerous spotters.
The rest of the month was about normal in terms of rainfall and the month ended as the eighth-rainiest September.
At Reading Regional Airport, the official National Weather Service site in Berks, the precipitation for the year is about 3 inches above normal. The county average as calculated by a division of the weather service, the Middle Atlantic River Forecast Center, is about 5 inches above normal.
The normal rainfall for September is up to 4.88 inches, the highest normal yet. And, that is ditto for the annual rainfall normal of 45.71 inches.
So, the bar is high now since normal is relative.
Normal is now considered the average of the years 1991 to 2020 and that period holds six of the 10 wettest Septembers on record, including No. 1 in 2018.
For temperatures, that September normal of 66.9 degrees is highest next to the temperature from the 1931-1960 data set, which was 67.1.
The 1991 to 2020 data holds four of the 10 warmest Septembers but the chilly conditions of the first seven years of the 1990s is enough to keep the average in second place. If the current pattern continues, the next set of normals, 2001-2030, might well be the warmest yet.
September weather in Berks
• 68.9°: Average temperature:
• 66.9°: Normal
• 8.22″: Rainfall
• 4.88″: Normal
90-degree days: 0 (Year: 34)
Rain: 4.95″ on the 1st (3.50, 1952)
Totals from the Berks Area Rainfall Networks
Pine Grove, 13.02; Geigertown, 12.55; Topton, 12.02; Wernersville (N), 12.14; Wernersville (S), 11.55; South Mountain, 11.55; Womelsdorf, 11.39; Scarlets Mill, 11.14; Mohnton (Northridge), 10.96; Shartlesville, 10.72; Bernville, 10.46; Henningsville, 10.42; Sinking Spring, 10.40; Hopewell Park, 10.29; Gilbertsville, 10.28; Gouglersville, 10.09; Newmanstown, 9.98; Midvale Manor, 9.97; Douglassville and Shillington, 9.66; Knauers, 9.59; Reading (Hillside), 9.56; Pikeville, 9.47; Wyomissing, 9.38; Mohnton (2), 9.37; Landis Store, 9.32; Reiffton, West Reading and Vinemont, 9.28; Reading (near City Park), 9.26; Bally, 9.13; Boyers Junction, 9.10; Lincoln Park, 9.09; Cornwall Terrace, 9.07; Wyomissing (Highlands), 9.04; New Morgan, 8.93; Muhlenberg Park, 8.89; Morgantown, 8.83; Cornwall Terrace (2), 8.77; Hamburg (N), 8.74; Cumru Township building, 8.69; Mohrsville, 8.60; Greenfields, 8.52; Blue Marsh Dam, 8.45; Reading (NW), 8.41; Adamstown, 8.38; Oley, 8.29; State Hill, 8.29; Lobachsville, 8.26; Bechtelsville, 8.22; Spring Ridge, 7.61; Boyertown, 7.52; Mertztown, 6.94; Windsor Township, 6.61; Pricetown, 6.60; and Mount Penn fire tower, 6.04.
10 Rainiest Septembers
• 12.35″ 1999
• 11.69″ 2011
• 10.34″ 1987
• 9.25″ 2003
• 9.05″ 1975
• 8.65″ 1907
• 8.40″ 1993
• 8.22″ 2021
• 8.03″ 1934 and 2018
Source: Berkshire mont