Temperature Norms for Harrison Month Average High Temperature Average Low Temperature January 45.99 26.32 February 50.22 29.72 March 59.44 38.07 April 70.16 48.92 May 76.75 55.90 June 83.90 63.37 July 89.03 68.26 August 88.51 66.58 September 80.59 59.11 October 70.65 48.78 November 58.59 39.23 December 48.21 31.66   Normal Yearly High Temperature Average - 68.49 Normal Yearly Low Temperature Average - 47.96   Precipitation Norms for Harrison Month Average Rainfall Amount - Inches January 2.65 February 2.84 March 4.18 April 4.38 May 5.00 June 4.19 July 2.99 August 3.45 September 4.04 October 3.75 November 4.51 December 3.54   Normal Yearly Average Precipitation (Inches) - 45.76