Monthly Humidity Averages for Massachusetts

The humidity averages for each month are listed below for places in Massachusetts. The tables give the daily averages along with highest and lowest 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.

All the numbers here are averages for the years 1961 to 1990.

Average Humidity

In this table, the Daily number for the month or year is the average of humidity readings taken every three hours throughout the day. Morning percentages are for 7 am and Afternoon measures are for 4 pm local standard time.

Average relative humidity (%) for Boston, Massachusetts

Daily		Morning	Afternoon
62	January	67	57
62	February	68	56
63	March	69	56
63	April	68	56
67	May	71	58
69	June	73	59
68	July	74	58
71	August	77	61
72	September	79	62
69	October	77	59
68	November	74	61
65	December	71	60
67	Annual	72	59

Average relative humidity (%) for Worcester, Massachusetts

Daily		Morning	Afternoon
65	January	70	59
64	February	71	56
63	March	70	54
60	April	68	49
64	May	70	51
69	June	74	57
70	July	76	58
73	August	79	61
75	September	81	62
69	October	78	57
71	November	77	62
70	December	75	64
68	Annual	74	58

Highest and Lowest Humidity

Below are the monthly and yearly averages for maximum and minimum humidity levels in Massachusetts. The hours when a month's highest and lowest humidity readings usually occur are given in local standard time.

Daily high and low relative humidity (%) averages in Boston, Massachusetts

High	Time		Low	Time
67.0	7 am	January	56.8	4 pm
67.6	7 am	February	55.6	4 pm
69.3	4 am	March	56.0	1 pm
71.1	4 am	April	54.9	1 pm
77.0	4 am	May	58.4	1 pm
80.0	4 am	June	58.0	1 pm
80.3	4 am	July	56.7	1 pm
82.1	4 am	August	58.6	1 pm
82.3	4 am	September	59.4	1 pm
77.5	4 am	October	57.0	1 pm
74.2	7 am	November	59.4	1 pm
70.6	7 am	December	59.2	1 pm
74.7	4 am	Annual	57.6	1 pm

Daily high and low relative humidity (%) averages in Worcester, Massachusetts

High	Time		Low	Time
69.9	7 am	January	58.1	1 pm
71.4	7 am	February	56.2	4 pm
69.9	7 am	March	53.5	4 pm
70.5	4 am	April	49.1	4 pm
75.3	4 am	May	51.4	4 pm
79.9	4 am	June	56.8	1 pm
81.5	4 am	July	57.0	1 pm
83.5	4 am	August	59.6	1 pm
84.4	4 am	September	60.8	1 pm
78.9	4 am	October	56.3	1 pm
77.2	7 am	November	61.1	1 pm
74.8	7 am	December	62.4	1 pm
76.2	4 am	Annual	57.0	1 pm