Washington weather by month
What a typical year looks like in Washington, Pennsylvania: average highs and lows, rain and snow, and the warmest and coldest days on record. No nearby active station has official 1991–2020 normals, so these are forecast.blue’s own averages computed from daily observations at Washington County Airport, 6 km from Washington, over its available record (2017–2026) — not an NCEI normal; records cover 2017–2026.
The year at a glance
- Precipitation a year
- 32.6 in828 mm
- Snow a year
- Rare
- Last spring freeze
- Apr 29
- First fall freeze
- Oct 17
- Heating degree days
- —
- Cooling degree days
- —
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 0°−18° (heating, 99%) and 91°33° (cooling, 1%).
Month by month
Washington in January
Highs average 37°3° and lows 20°−6°, with 2.6 in66 mm of precipitation in a typical January.
- Record high
- 72°22° (2020)
- Record low
- −18°−28° (2026)
- Heating degree days
- —
- Cooling degree days
- —
Washington in February
Highs average 45°7° and lows 24°−4°, with 3.2 in81 mm of precipitation in a typical February.
- Record high
- 78°26° (2018)
- Record low
- −8°−22° (2026)
- Heating degree days
- —
- Cooling degree days
- —
Washington in March
Highs average 54°12° and lows 31°0°, with 3.3 in84 mm of precipitation in a typical March.
- Record high
- 85°29° (2026)
- Record low
- 5°−15° (2022)
- Heating degree days
- —
- Cooling degree days
- —
Washington in April
Highs average 63°17° and lows 40°4°, with 3.5 in89 mm of precipitation in a typical April.
- Record high
- 85°29° (2026)
- Record low
- 19°−7° (2021)
- Heating degree days
- —
- Cooling degree days
- —
Washington in May
Highs average 72°22° and lows 50°10°, with 3.5 in89 mm of precipitation in a typical May.
- Record high
- 88°31° (2018)
- Record low
- 25°−4° (2020)
- Heating degree days
- —
- Cooling degree days
- —
Washington in June
Highs average 80°27° and lows 58°14°, with 2.8 in71 mm of precipitation in a typical June.
- Record high
- 93°34° (2024)
- Record low
- 37°3° (2020)
- Heating degree days
- —
- Cooling degree days
- —
Washington in July
Highs average 84°29° and lows 63°17°, with 2.4 in61 mm of precipitation in a typical July.
- Record high
- 94°34° (2018)
- Record low
- 49°9° (2024)
- Heating degree days
- —
- Cooling degree days
- —
Washington in August
Highs average 82°28° and lows 61°16°, with 2.7 in69 mm of precipitation in a typical August.
- Record high
- 95°35° (2024)
- Record low
- 43°6° (2024)
- Heating degree days
- —
- Cooling degree days
- —
Washington in September
Highs average 77°25° and lows 54°12°, with 2 in51 mm of precipitation in a typical September.
- Record high
- 93°34° (2018)
- Record low
- 32°0° (2020)
- Heating degree days
- —
- Cooling degree days
- —
Washington in OctoberThis month
Highs average 66°19° and lows 43°6°, with 2.4 in61 mm of precipitation in a typical October.
- Record high
- 90°32° (2019)
- Record low
- 25°−4° (2018)
- Heating degree days
- —
- Cooling degree days
- —
Washington in November
Highs average 52°11° and lows 32°0°, with 2.2 in56 mm of precipitation in a typical November.
- Record high
- 80°27° (2024)
- Record low
- 10°−12° (2019)
- Heating degree days
- —
- Cooling degree days
- —
Washington in December
Highs average 44°6° and lows 27°−3°, with 2 in51 mm of precipitation in a typical December.
- Record high
- 68°20° (2024)
- Record low
- −4°−20° (2022)
- Heating degree days
- —
- Cooling degree days
- —
Pittsburgh WSO City station, 1874–1979: records and averages
This station is no longer reporting, but its 1874–1979 record is the longest and most local history available. These are its own averages over its own period of record — not NCEI normals, and not the same station as the computed averages above.
January
Average high 39°4°, low 24°−5°, 2.9 in74 mm precipitation.
Record high 77°25° (1950); record low −14°−26° (1977).
February
Average high 40°4°, low 24°−4°, 2.5 in64 mm precipitation.
Record high 77°25° (1900); record low −20°−29° (1899).
March
Average high 49°10°, low 32°0°, 3.3 in84 mm precipitation.
Record high 84°29° (1929); record low 1°−17° (1900).
April
Average high 61°16°, low 42°5°, 3.1 in79 mm precipitation.
Record high 91°33° (1976); record low 11°−12° (1923).
May
Average high 72°22°, low 52°11°, 3.3 in84 mm precipitation.
Record high 95°35° (1875); record low 27°−3° (1876).
June
Average high 81°27°, low 61°16°, 3.7 in94 mm precipitation.
Record high 99°37° (1952); record low 39°4° (1879).
July
Average high 84°29°, low 65°18°, 3.9 in99 mm precipitation.
Record high 103°39° (1881); record low 49°9° (1894).
August
Average high 83°28°, low 63°17°, 3.3 in84 mm precipitation.
Record high 103°39° (1918); record low 45°7° (1890).
September
Average high 76°25°, low 57°14°, 2.7 in69 mm precipitation.
Record high 102°39° (1881); record low 33°1° (1942).
October
Average high 65°18°, low 46°8°, 2.5 in64 mm precipitation.
Record high 91°33° (1879); record low 20°−7° (1887).
November
Average high 51°11°, low 36°2°, 2.4 in61 mm precipitation.
Record high 83°28° (1961); record low 1°−17° (1929).
December
Average high 41°5°, low 28°−2°, 2.7 in69 mm precipitation.
Record high 73°23° (1885); record low −9°−23° (1880).