Rainfall/ Precipitation in Boston, Massachusetts, Usa

• Boston, Massachusetts receives 1054.3 mm (41.5 in) of rainfall per year, or 87.9 mm (3.5 in) per month.
• On average there are 128 days per year with more than 0.1 mm (0.004 in) of rainfall (precipitation) or 10.7 days with a quantity of rain, sleet, snow etc. per month.
• The driest weather is in July when an average of 72.1 mm (2.8 in) of rainfall (precipitation) occurs.
• The wettest weather is in November when an average of 107.2 mm (4.2 in) of rainfall (precipitation) occurs.

Precipitation Table

	Climate Variable	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec		Annual
	Average Precipitation mm (in)	91.2 (3.59)	91.9 (3.6)	93.7 (3.7)	91.4 (3.6)	82.6 (3.3)	78.5 (3.1)	72.1 (2.8)	82.3 (3.2)	77.7 (3.1)	83.8 (3.3)	107.2 (4.2)	101.9 (4)		1054.3 (41.5)
	Precipitation Litres/m² (Gallons/ft²)	91.2 (2.24)	91.9 (2.25)	93.7 (2.3)	91.4 (2.24)	82.6 (2.03)	78.5 (1.93)	72.1 (1.77)	82.3 (2.02)	77.7 (1.91)	83.8 (2.06)	107.2 (2.63)	101.9 (2.5)		1054.3 (25.86)
	Number of Wet Days (probability of rain on a day)	12 (39%)	11 (39%)	12 (39%)	12 (40%)	12 (39%)	11 (37%)	10 (32%)	10 (32%)	9 (30%)	9 (29%)	10 (33%)	10 (32%)		128 (35%)
	Percentage of Sunny (Cloudy) Daylight Hours	52 (48)	55 (45)	58 (42)	53 (47)	61 (39)	65 (35)	71 (29)	68 (32)	65 (35)	65 (35)	55 (45)	59 (41)		62 (38)