SEPTEMBER CHICAGO NORMALS FOR TEMPERATURE, PRECIPITATION, SNOWFALL (1981-2010)

JAN  FEB  MAR  APR  MAY  JUN  JUL  AUG  SEP  OCT  NOV  DEC

Day of Month	High	Low	Average	HDD	CDD	Precipitation
1	80	60	70	1	6	0.12
2	80	60	70	1	6	0.12
3	79	60	69	1	5	0.11
4	79	59	69	1	5	0.12
5	79	59	69	1	5	0.11
6	78	59	68	1	5	0.12
7	78	58	68	1	5	0.11
8	78	58	68	2	4	0.11
9	78	57	67	2	4	0.11
10	77	57	67	2	4	0.10
11	77	56	67	2	4	0.11
12	76	56	66	2	4	0.10
13	76	56	66	3	3	0.11
14	76	55	65	3	3	0.10
15	75	55	65	3	3	0.10
16	75	54	65	3	3	0.11
17	75	54	64	3	3	0.10
18	74	53	64	4	2	0.10
19	74	53	63	4	2	0.11
20	73	52	63	4	2	0.11
21	73	52	62	5	2	0.11
22	72	51	62	5	2	0.11
23	72	51	61	5	2	0.10
24	72	51	61	6	2	0.11
25	71	50	61	6	1	0.11
26	71	50	60	6	1	0.11
27	70	49	60	7	1	0.10
28	70	49	59	7	1	0.09
29	69	48	59	7	1	0.10
30	69	48	58	8	1	0.09
MONTH	74.8	54.3	64.6	105	92	3.2

HDD = A Heating Degree Day represents the number of degree(s) that the mean temperature for the day is below 65 degrees during a day.

CDD = A Cooling Degree Day represents the number of degree(s) that the mean temperature for the day is above 65 degrees during a day.

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