Cornwall September Weather

Typical Cornwall September Weather 1991–2020
Average daily high	72.3 °F
Average daily low	49.7 °F
Average monthly precipitation	3.2 inches
Average monthly snow	none

Cornwall September Weather Records 1894–2023
Highest temperature	96 °F	September 10, 2002
Lowest temperature	22 °F	September 2, 2017
Highest daily low	78 °F	September 15, 1915
Lowest daily high	46 °F	September 27, 1939
Hottest average temperature	7.7 °F above average	1961
Coldest average temperature	-5.3 °F below average	1956
Most daily precipitation	4.0 inches	September 17, 1999
Most monthly precipitation	8.2 inches	1999
Most daily snow	none	-
Most monthly snow	none	-

Day	Average (°F)		Record (°F)
	High	Low	High	Low
September 1	76.5	53.8	94	37
September 2	76.3	53.5	94	22
September 3	76.0	53.3	95	34
September 4	75.8	53.1	96	39
September 5	75.5	52.7	95	35
September 6	75.2	52.3	92	32
September 7	75.0	52.1	94	35
September 8	74.8	51.9	93	35
September 9	74.5	51.6	92	33
September 10	74.1	51.3	96	32
September 11	73.8	50.9	94	33
September 12	73.5	50.5	91	27
September 13	73.2	50.3	90	32
September 14	72.9	50.1	91	29
September 15	72.5	49.8	93	32
September 16	72.1	49.5	93	29
September 17	71.6	49.2	90	30
September 18	71.2	48.8	90	33
September 19	70.7	48.4	87	29
September 20	70.2	48.1	88	28
September 21	69.7	47.7	90	27
September 22	69.2	47.3	88	27
September 23	68.7	46.8	90	28
September 24	68.3	46.4	88	23
September 25	67.8	45.9	91	31
September 26	67.5	45.7	90	27
September 27	67.2	45.5	88	23
September 28	66.8	45.1	87	24
September 29	66.3	44.6	83	22
September 30	65.9	44.2	85	22