Rochester - Average temperatures (1991-2020) Month Min Max Mean Min Max Mean ('C) (C) (C) (OF) (OF) (OF) January -7.2 0.8 -3.2 19 33 26.2 February -6.9 1.8 -2.6 20 35 27.4 March -2.9 6.4 1.8 27 44 35.2 April 2.8 13.7 8.3 37 57 46.8 May 9 20.8 14.9 48 69 58.8 June 14.1 25-5 19.8 57 78 67.6 July 16.8 28.1 22.4 62 82 72.4 August 16.1 26.9 21.5 61 80 70.8 September 12 23.1 17.6 54 74 63.6 October 6.3 16.2 11.2 43 61 52.2 November 1.1 9.5 5-3 34 49 41.6 December -3.7 3.6 O 25 38 32 Year 4.9 14.8 9.8 40.8 58.6 49.5