Weather on September 15 at Indiana Dunes
Indiana Dunes National Park
Based on 55 years of data from Gary, IN
Planning Your Visit
September 15th in Indiana Dunes National Park (via Gary, IN) typically brings pleasant fall weather, with average highs around 75°F and lows near 55°F. Over 55 years of records, the warmest September 15th was in 1991 (81°F average), while the coldest was 1984 (54°F) — a 27°F range across recorded history. Rain or other precipitation has occurred on about 25% of September 15th dates historically, with the wettest September 15th recording 7.8" of rain. The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
Planning for September 15th in Indiana Dunes? Great weather for outdoor activities.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 79°F | 64°F | 0" | 0" |
| 2024 | 88°F | 63°F | 0" | 0" |
| 2023 | 69°F | 50°F | 0" | 0" |
| 2022 | 74°F | 54°F | 0" | 0" |
| 2021 | 87°F | 65°F | 0" | 0" |
| 2020 | 73°F | 56°F | 0" | 0" |
| 2019 | 78°F | 62°F | -- | -- |
| 2018 | 79°F | 59°F | -- | -- |
| 2017 | 74°F | 57°F | 0" | 0" |
| 2016 | 72°F | 59°F | 0" | 0" |
| 2015 | 79°F | 58°F | 0" | 0" |
| 2014 | 65°F | 44°F | 0.1" | 0" |
| 2013 | 70°F | 48°F | 0" | 0" |
| 2012 | 73°F | 47°F | 0" | 0" |
| 2011 | 66°F | 54°F | 0.36" | 0" |
| 2010 | 74°F | 56°F | 0" | 0" |
| 2009 | 81°F | 57°F | 0" | 0" |
| 2008 | 67°F | 59°F | 7.8" | 0" |
| 2007 | 65°F | 51°F | 0" | 0" |
| 2006 | 70°F | 55°F | 0" | 0" |
| 2005 | 71°F | 56°F | 0" | 0" |
| 2004 | 84°F | 67°F | 0" | 0" |
| 2003 | 74°F | 54°F | 0.13" | 0" |
| 2002 | 86°F | 66°F | 0.03" | 0" |
| 2001 | 64°F | 48°F | 0" | 0" |
| 2000 | 67°F | 54°F | 0.2" | 0" |
| 1999 | 69°F | 48°F | 0" | 0" |
| 1998 | 84°F | 70°F | 0.03" | 0" |
| 1997 | 82°F | 60°F | 0" | 0" |
| 1996 | 65°F | 52°F | 0" | 0" |
| 1995 | 85°F | 61°F | 0.36" | 0" |
| 1994 | 89°F | 69°F | 0" | 0" |
| 1993 | 60°F | 52°F | 1.09" | 0" |
| 1992 | 82°F | 65°F | 0.18" | 0" |
| 1991 | 90°F | 73°F | 0" | 0" |
| 1990 | 71°F | 54°F | 0" | 0" |
| 1989 | 67°F | 48°F | 0" | 0" |
| 1988 | 78°F | 56°F | 0" | 0" |
| 1987 | 75°F | 59°F | 0" | 0" |
| 1986 | 81°F | 53°F | 0" | 0" |
| 1985 | 73°F | 42°F | 0" | 0" |
| 1984 | 63°F | 45°F | 1.65" | 0" |
| 1983 | 68°F | 45°F | 0.51" | 0" |
| 1982 | 72°F | 63°F | 0" | 0" |
| 1981 | 80°F | 48°F | 0" | 0" |
| 1980 | 65°F | 55°F | 0.08" | 0" |
| 1979 | 73°F | 45°F | 0" | 0" |
| 1978 | 88°F | 56°F | 0" | 0" |
| 1977 | 77°F | 55°F | 3.18" | 0" |
| 1976 | 84°F | 61°F | 0" | 0" |
| 1975 | 70°F | 50°F | 0" | 0" |
| 1974 | 76°F | 50°F | 0" | 0" |
| 1973 | 72°F | 51°F | 0" | 0" |
| 1972 | 75°F | 48°F | 0" | 0" |
| 1971 | 87°F | 53°F | 0" | 0" |