Drought in Custer County, MT: 5.8 years in 10 since 2000

5.8 years in 10

Custer County, MT: 15 of 26 full years had 13+ weeks in drought. More drought-prone than most US counties.

20002025

Drought years: 2000 (14 wk), 2001 (26 wk), 2002 (53 wk), 2003 (52 wk), 2004 (52 wk), 2005 (23 wk), 2006 (24 wk), 2007 (25 wk), 2008 (21 wk), 2012 (21 wk), 2017 (27 wk), 2021 (49 wk), 2022 (23 wk), 2024 (15 wk) and 2025 (26 wk). Not a single drought week in 2009, 2010, 2011, 2014, 2015, 2016, 2019, 2020 and 2023.

Plan for drought as normal: shrink the lawn, go drip and natives

Drought is the normal state of things here. Most of the yard goes to natives and gravel on drip; any grass that stays is a small, tough patch.

If you are replacing turf, plant natives in fall so roots set before the Oct peak, and check your water utility for a turf-removal rebate before you dig.

Against the rest of MT

22nd most drought-prone of 56 MT counties; the MT middle is 5.4 in 10. Closest on the list: Liberty County (5.8 in 10) and Meagher County (5.4 in 10). Driest in MT: Glacier County (6.9 in 10). Least drought: Garfield County (3.8 in 10).

When in the year it hits

Most often in Oct (43% of weeks), then Apr (40%) and Mar (38%). Least in Jun (28%). May to September averages 30%.

35 Jan
37 Feb
38 Mar
40 Apr
33 May
28 Jun
28 Jul
30 Aug
30 Sep
43 Oct
38 Nov
37 Dec

The worst year: 2004

2004: 52 weeks in drought, peaking at D4 exceptional. Across 1,401 weekly maps: 34.6% of all weeks at D1 or worse, 23.1% at D2, 7.9% at D3, 60 weeks with some of the county in D4. Longest unbroken spell: 193 weeks, Oct 2, 2001 to Jun 7, 2005.

Lately

Last drought year: 2025, 26 weeks. 2016-2025: 5 in 10, against 6.3 in 10 for 2000-2015, about the same. So far in 2026: 25 of 44 weeks in drought, through Nov 3, 2026.