Relative Humidity in September at US Cities

The average humidity in September is listed here for the largest cities in the United States. The tables below give this month's daily averages along with morning and afternoon relative humidity levels.

Relative humidity measures the actual amount of moisture in the air as a percentage of the maximum amount of moisture the air can hold.

For each city, the Daily number gives the average of humidity readings taken every three hours throughout the day. Morning values are recorded between 4 and 6 am local standard time, when usually temperatures are coolest and humidity highest. Afternoon humidity percentages are readings taken between 3 and 5 pm local standard time, when normally the day's temperature peaks and relative humidity reaches its lowest point. All the figures are averages for the years 1961 to 1990.

Average Relative Humidity (%) in September
Daily	City	Morning	Afternoon
74	Atlanta, Georgia	87	57
68	Austin, Texas	86	49
71	Baltimore, Maryland	85	54
74	Birmingham, Alabama	88	55
72	Boston, Massachusetts	82	62
74	Buffalo, New York	85	60
73	Charlotte, North Carolina	87	55
71	Chicago, Illinois	85	55
73	Cincinnati, Ohio	86	54
74	Cleveland, Ohio	84	60
73	Columbus, Ohio	86	54
67	Dallas, Texas	85	48
50	Denver, Colorado	69	34
73	Detroit, Michigan	87	55
50	Fresno, California	65	26
76	Grand Rapids, Michigan	88	59
73	Hartford, Connecticut	88	55
66	Honolulu, Hawaii	73	54
77	Houston, Texas	93	57

Daily	City	Morning	Afternoon
74	Indianapolis, Indiana	89	54
81	Jacksonville, Florida	93	66
70	Kansas City, Missouri	86	53
25	Las Vegas, Nevada	34	17
74	Los Angeles, California	83	67
73	Louisville, Kentucky	86	55
71	Memphis, Tennessee	86	55
78	Miami, Florida	88	69
75	Milwaukee, Wisconsin	87	63
71	Minneapolis, Minnesota	85	54
74	Nashville, Tennessee	90	54
78	New Orleans, Louisiana	89	63
68	New York, New York	78	56
67	Oklahoma City, Oklahoma	83	49
79	Orlando, Florida	92	65
72	Philadelphia, Pennsylvania	85	55
36	Phoenix, Arizona	50	23
72	Pittsburgh, Pennsylvania	85	55

Daily	City	Morning	Afternoon
69	Portland, Oregon	86	48
73	Providence, Rhode Island	86	59
77	Raleigh, North Carolina	92	57
77	Richmond, Virginia	91	57
77	Rochester, New York	89	61
57	Sacramento, California	77	31
46	Salt Lake City, Utah	61	29
68	San Antonio, Texas	86	48
73	San Diego, California	80	65
72	San Francisco, California	83	58
73	Seattle, Washington	86	57
72	St. Louis, Missouri	89	53
78	Tampa, Florida	90	63
42	Tucson, Arizona	51	27
70	Tulsa, Oklahoma	85	55
74	Virginia Beach, Virginia	85	62
70	Washington, DC	82	55

Average Relative Humidity in September at US Cities

Reference

More US City Weather Information