Most Monthly Precipitation in Interior History

This is a list of the largest monthly precipitation totals ever recorded in Interior, South Dakota history from 1949–2024.

What Was the Wettest Month in Interior History?

According to NOAA records, the most precipitation that Interior, South Dakota has ever received in a single month is 9.5 inches which occurred in May 2015.

Month to date though April 23, 2024: 1.5 inches

Interior Most Rain in One Month

Rank	Precipitation	Month
1	9.5 inches	May 2015
2	8.3 inches	July 2019
3	7.8 inches	June 1991
4	7.3 inches	May 1982
5	7.2 inches	June 1967
6	7.2 inches	May 2019
7	6.8 inches	May 1996
8	6.7 inches	October 2013
9	6.5 inches	May 1991
10	6.5 inches	June 1999
11	6.4 inches	June 1962
12	6.3 inches	May 1965
13	6.3 inches	May 1995
14	6.2 inches	June 2018
15	6.0 inches	June 2014
16	6.0 inches	June 2015
17	5.9 inches	May 1978
18	5.8 inches	July 1958
19	5.8 inches	June 1964
20	5.7 inches	June 1998