Topography & Climate

General Physical Description

Franklin County is Virginia’s seventh largest county, containing 711.6 total square miles within its borders. The county falls along the eastern foothills of the Blue Ridge Mountains and the terrain is largely mountainous or rolling hills. Much of the county is under tree canopy with some large areas of open land for pasture and other agricultural or light industrial uses. Franklin County also contains 257 miles of shoreline along Smith Mountain Lake and 34 miles of shoreline along Philpott Lake.


There is a total of 2,907 feet of elevation variation in Franklin County. The lowest point in the county is 664 feet above sea level. This lowest point is located along the border with Pittsylvania County where the Pigg River crosses the county line. The highest point in the county is 3,571 feet above sea level. This highest point is located at Cahas Knob, the highest point on Cahas Mountain in the northern portion of the County. Elevations in the Town of Rocky Mount range from 964 feet to 1,934 feet above sea level, while elevations in the Town of Boones Mill range from 1,084 feet to 1,356 feet above sea level.



  • Average January High Temperature - 47.9 degrees
  • Average January Low Temperature - 25.9 degrees
  • Average July High Temperature - 86.6 degrees
  • Average July Low Temperature - 62.8 degrees
  • Mean Annual Temperature - 56.0 degrees


  • Average Annual Rainfall - 44 inches
  • Average Annual Snowfall - 14 inches
  • Average Growing Season - 180 days
  • Average Relative Humidity - 66%
  • Frost-Free Nights - Average April 20 through October 16

Wind & Air

  • Air Quality - Franklin County is classified as an attainment area for all pollutants by both State and Federal agencies
  • Prevailing Winds - Westerly

Source: National Oceanic and Atmospheric Administration (NOAA)