Castle Rock Average Rainfall by Month

This page shows the average precipitation (including snowfall) in each month of the year in Castle Rock, Colorado. It is based on NOAA data for the years 1991–2020.

Average temperature by month

What's the Rainiest Month in Castle Rock?

In Castle Rock, August has the greatest precipitation of any month. On average, Castle Rock gets 2.5 inches of precipitation in August.

August is also the month where rain is most common. 32.4% of days in August will have at least some rain.

What's the Driest Month in Castle Rock?

In Castle Rock, January has the least precipitation of any month. On average, Castle Rock gets 0.59 inches of precipitation in January.

January is also the month where rain is least common. 13.3% of days in January will have measurable rain or snow.

Month	Precipitation	% Chance
January	0.59 in	13.3
February	0.73 in	17.0
March	1.49 in	16.0
April	2.09 in	21.4
May	2.01 in	26.9
June	2.28 in	25.8
July	2.25 in	26.2
August	2.50 in	32.4
September	1.36 in	19.3
October	0.83 in	14.1
November	0.67 in	13.8
December	0.60 in	15.0
Year	17.24 in	20.1

Weather Station Details

Years	Station	Coordinates
1893–2024	Castle Rock	location