Drought in Hamilton County, IL: 0.4 years in 10 since 2000

0.4 years in 10

Hamilton County, IL: 1 of 26 full years had 13+ weeks in drought. Less drought-prone than most US counties.

1. 1
2. 8
3. 10
4. 1
5. 0
6. 2
7. 0
8. 11
9. 0
10. 0
11. 7
12. 0
13. 19
14. 0
15. 0
16. 0
17. 0
18. 0
19. 0
20. 4
21. 1
22. 0
23. 12
24. 10
25. 4
26. 7

20002025

Drought years: 2012 (19 wk). Not a single drought week in 2004, 2006, 2008, 2009, 2011, 2013, 2014, 2015, 2016, 2017, 2018 and 2021.

A regular lawn is fine here; plan for the odd dry year

Real droughts are rare here. A smart controller that skips watering after rain covers the odd dry year.

You can keep a regular lawn. Worth doing: a rain-sensing or smart controller, and deeper, less frequent watering if Oct turns dry.

Against the rest of IL

101st most drought-prone of 102 IL counties; the IL middle is 2.3 in 10. Closest on the list: Saline County (0.4 in 10) and Edwards County (0.4 in 10). Driest in IL: Hancock County (3.8 in 10). Least drought: Edwards County (0.4 in 10).

When in the year it hits

Most often in Oct (18% of weeks), then Sep (16%) and Aug (11%). Least in Mar (2%). May to September averages 10%.

1. 5 Jan
2. 4 Feb
3. 2 Mar
4. 3 Apr
5. 6 May
6. 8 Jun
7. 9 Jul
8. 11 Aug
9. 16 Sep
10. 18 Oct
11. 10 Nov
12. 7 Dec

The worst year: 2012

2012: 19 weeks in drought, peaking at D4 exceptional. Across 1,401 weekly maps: 8.1% of all weeks at D1 or worse, 2.1% at D2, 0.4% at D3, 6 weeks with some of the county in D4. Longest unbroken spell: 19 weeks, May 29, 2012 to Oct 2, 2012.

Lately

Last drought year: 2012, 19 weeks. 2016-2025: 0 in 10, against 0.6 in 10 for 2000-2015, about the same. So far in 2026: 17 of 44 weeks in drought, through Nov 3, 2026.

Further reading

Hamilton County lands on the plan covered in keeping a regular lawn. Its worst year, 2012, was one of the worst nationally too; see the worst years since 2000. How each of Hamilton County's 1,401 weeks was judged: how drought is counted.