Geography According to the U.S. Census Bureau, the county has a total area of , of which is land and (1.5%) is water. It has a humid continental climate (Dfa/Dfb) and average monthly temperatures in Sharon range from 27.1 °F in January to 72.2 °F in July, while in Mercer borough they range from 25.4 °F in January to 70.1 °F in July. Mercer County is one of the 423 counties served by the Appalachian Regional Commission, and it is identified as part of the "Midlands" by Colin Woodard in his book American Nations: A History of the Eleven Rival Regional Cultures of North America.
Geography According to the U.S. Census Bureau, the county has a total area of , of which is land and (1.5%) is water. It has a humid continental climate (Dfa/Dfb) and average monthly temperatures in Sharon range from 27.1 °F in January to 72.2 °F in July, while in Mercer borough they range from 25.4 °F in January to 70.1 °F in July. Mercer County is one of the 423 counties served by the Appalachian Regional Commission and it is identified as part of the "Midlands" by Colin Woodard in his book American Nations: A History of the Eleven Rival Regional Cultures of North America.