What is the hottest month in Allegheny County, PA?

July is the warmest month, with a normal high of 85°F at Emsworth L/D Ohio Rvr.

What is the coldest month in Allegheny County, PA?

January is the coldest month, with a normal low of 21°F.

What is the wettest month in Allegheny County, PA?

July has the most precipitation on average, about 3.64 inches.

Checked Oct 25, 2026

Allegheny County, PA Climate

1991 to 2020 normals at Emsworth L/D Ohio Rvr, 6.4 mi from the center of Allegheny County, elevation 717 ft.

Average weather by month

Select a month for daily normals and last year's weather

Month	High	Low	Precip.	Snow
January	39°	21°	3.36 in	--
February	42°	22°	2.78 in	--
March	51°	29°	3.18 in	--
April	64°	39°	3.22 in	--
May	74°	50°	3.52 in	--
June	81°	59°	3.53 in	--
July	85°	64°	3.64 in	--
August	84°	62°	3.25 in	--
September	78°	55°	3.19 in	--
October	66°	44°	2.80 in	--
November	54°	33°	2.83 in	--
December	43°	26°	3.02 in	--
Year	63°		38.32 in	--

Frequently asked questions

What is the hottest month in Allegheny County, PA?: July is the warmest month, with a normal high of 85°F at Emsworth L/D Ohio Rvr.
What is the coldest month in Allegheny County, PA?: January is the coldest month, with a normal low of 21°F.
What is the wettest month in Allegheny County, PA?: July has the most precipitation on average, about 3.64 inches.

Today

Allegheny County, PA forecast

Data sources

U.S. Climate Normals 1991-2020NOAA National Centers for Environmental Information
U.S. Climate Normals 1991-2020 (daily) and GHCN-Daily via Access Data ServiceNOAA National Centers for Environmental Information

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About this data

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