Weather on August 18 at Indiana Dunes
Indiana Dunes National Park
Based on 55 years of data from Gary, IN
Planning Your Visit
August 18th in Indiana Dunes National Park (via Gary, IN) typically brings warm summer weather, with average highs around 82°F and lows near 62°F. Over 55 years of records, the warmest August 18th was in 1988 (87°F average), while the coldest was 1981 (59°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 29% of August 18th dates historically, with the wettest August 18th recording 9.65" of rain. The last decade has been 3.5°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.5°F warmer on this date compared to 20-30 years ago.
Planning for August 18th in Indiana Dunes? Stay hydrated and seek shade during peak afternoon hours.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 84°F | 72°F | -- | 0" |
| 2024 | 77°F | 68°F | -- | 0" |
| 2023 | 78°F | 57°F | 1.14" | 0" |
| 2022 | 77°F | 55°F | 0" | 0" |
| 2021 | 83°F | 69°F | -- | -- |
| 2020 | 79°F | 59°F | 0" | 0" |
| 2019 | 84°F | 67°F | -- | -- |
| 2018 | 79°F | 66°F | -- | -- |
| 2017 | 82°F | 68°F | 0" | 0" |
| 2016 | 85°F | 69°F | 0.53" | 0" |
| 2015 | 86°F | 65°F | 6.2" | 0" |
| 2014 | 75°F | 66°F | 0" | 0" |
| 2013 | 80°F | 57°F | 0" | 0" |
| 2012 | 72°F | 49°F | 0" | 0" |
| 2011 | 82°F | 63°F | 0" | 0" |
| 2010 | 76°F | 65°F | 0.3" | 0" |
| 2009 | 86°F | 70°F | 0.25" | 0" |
| 2008 | 82°F | 63°F | 0" | 0" |
| 2007 | 76°F | 56°F | 0" | 0" |
| 2006 | 84°F | 67°F | 0.05" | 0" |
| 2005 | 80°F | 67°F | 0" | 0" |
| 2004 | 81°F | 61°F | 3.4" | 0" |
| 2003 | 83°F | 62°F | 0" | 0" |
| 2002 | 84°F | 64°F | 0" | 0" |
| 2001 | 78°F | 62°F | 0" | 0" |
| 2000 | 77°F | 61°F | 0.84" | 0" |
| 1999 | 80°F | 52°F | 2.11" | 0" |
| 1998 | 78°F | 59°F | 0" | 0" |
| 1997 | 69°F | 53°F | -- | 0" |
| 1996 | 78°F | 60°F | 0.84" | 0" |
| 1995 | 89°F | 71°F | 1.42" | 0" |
| 1994 | 80°F | 54°F | 0" | 0" |
| 1993 | 85°F | 63°F | 0" | 0" |
| 1992 | 77°F | 53°F | 0.23" | 0" |
| 1991 | 84°F | 60°F | 0.13" | 0" |
| 1990 | 88°F | 68°F | 9.65" | 0" |
| 1989 | 77°F | 55°F | 0" | 0" |
| 1988 | 99°F | 75°F | 0" | 0" |
| 1987 | 85°F | 61°F | 0.48" | 0" |
| 1986 | 82°F | 58°F | 0" | 0" |
| 1985 | 85°F | 71°F | 0" | 0" |
| 1984 | 85°F | 65°F | 0" | 0" |
| 1983 | 86°F | 70°F | 0" | 0" |
| 1982 | 84°F | 52°F | 0" | 0" |
| 1981 | 74°F | 44°F | 0" | 0" |
| 1980 | 83°F | -- | 0" | 0" |
| 1979 | 78°F | 64°F | 1.83" | 0" |
| 1978 | 88°F | 70°F | 0" | 0" |
| 1977 | 74°F | 53°F | 0" | 0" |
| 1976 | 81°F | 50°F | 0" | 0" |
| 1975 | 82°F | 58°F | 0" | 0" |
| 1974 | 85°F | 57°F | 0" | 0" |
| 1973 | 87°F | 63°F | 0" | 0" |
| 1972 | 93°F | 73°F | 0" | 0" |
| 1971 | 86°F | 53°F | 0" | 0" |