Atglen weather by month
What a typical year looks like in Atglen, Pennsylvania: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Octoraro Lake, 18 km from Atglen; records cover 1978–2026.
The year at a glance
- Precipitation a year
- 48.4 in1230 mm
- Snow a year
- 18 in46 cm
- Last spring freeze
- Apr 25
- First fall freeze
- Oct 19
- Heating degree days
- 5,358
- Cooling degree days
- 898
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 4°−16° (heating, 99%) and 95°35° (cooling, 1%).
Month by month
Atglen in January
Highs average 39°4° and lows 22°−5°, with 3.5 in88 mm of precipitation and 5 in13 cm of snow in a typical January.
- Record high
- 72°22° (2002)
- Record low
- −19°−28° (1984)
- Heating degree days
- 1072
- Cooling degree days
- 0
Atglen in February
Highs average 42°5° and lows 23°−5°, with 2.9 in73 mm of precipitation and 7 in18 cm of snow in a typical February.
- Record high
- 78°26° (2018)
- Record low
- −17°−27° (1996)
- Heating degree days
- 916
- Cooling degree days
- 0
Atglen in March
Highs average 51°10° and lows 31°−1°, with 4.2 in108 mm of precipitation and 2.6 in6.6 cm of snow in a typical March.
- Record high
- 91°33° (1998)
- Record low
- −4°−20° (1984)
- Heating degree days
- 753
- Cooling degree days
- 0
Atglen in April
Highs average 63°17° and lows 40°4°, with 3.8 in96 mm of precipitation and 0.1 in0.3 cm of snow in a typical April.
- Record high
- 95°35° (2002)
- Record low
- 10°−12° (2001)
- Heating degree days
- 412
- Cooling degree days
- 8
Atglen in May
Highs average 72°22° and lows 50°10°, with 3.6 in90 mm of precipitation in a typical May.
- Record high
- 95°35° (2000)
- Record low
- 23°−5° (2002)
- Heating degree days
- 166
- Cooling degree days
- 51
Atglen in June
Highs average 80°27° and lows 60°15°, with 4.5 in113 mm of precipitation in a typical June.
- Record high
- 99°37° (1994)
- Record low
- 34°1° (1992)
- Heating degree days
- 24
- Cooling degree days
- 177
Atglen in July
Highs average 85°29° and lows 65°18°, with 4.5 in115 mm of precipitation in a typical July.
- Record high
- 103°39° (1995)
- Record low
- 42°6° (2000)
- Heating degree days
- 1
- Cooling degree days
- 303
Atglen in August
Highs average 83°28° and lows 63°17°, with 4.7 in120 mm of precipitation in a typical August.
- Record high
- 104°40° (2001)
- Record low
- 36°2° (1982)
- Heating degree days
- 5
- Cooling degree days
- 250
Atglen in September
Highs average 76°24° and lows 56°13°, with 5.2 in131 mm of precipitation in a typical September.
- Record high
- 97°36° (1983)
- Record low
- 31°−1° (1990)
- Heating degree days
- 73
- Cooling degree days
- 97
Atglen in OctoberThis month
Highs average 65°18° and lows 44°7°, with 4.1 in105 mm of precipitation in a typical October.
- Record high
- 92°33° (2019)
- Record low
- 12°−11° (2001)
- Heating degree days
- 347
- Cooling degree days
- 12
Atglen in November
Highs average 53°12° and lows 33°1°, with 3.4 in86 mm of precipitation and 0.3 in0.8 cm of snow in a typical November.
- Record high
- 81°27° (2024)
- Record low
- 11°−12° (1997)
- Heating degree days
- 657
- Cooling degree days
- 0
Atglen in December
Highs average 43°6° and lows 27°−3°, with 4.1 in105 mm of precipitation and 3 in8 cm of snow in a typical December.
- Record high
- 75°24° (1998)
- Record low
- −4°−20° (1989)
- Heating degree days
- 932
- Cooling degree days
- 0