Weather on September 18 at Biscayne
Biscayne National Park
Based on 55 years of data from Miami, FL
Planning Your Visit
September 18th in Biscayne National Park (via Miami, FL) typically brings warm fall weather, with average highs around 87°F and lows near 77°F. Over 55 years of records, the warmest September 18th was in 1995 (87°F average), while the coldest was 1985 (73°F) — a 14°F range across recorded history. Rain or other precipitation has occurred on about 44% of September 18th dates historically, with the wettest September 18th recording 7.32" of rain. The last decade has been 1.4°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.4°F warmer on this date compared to 20-30 years ago.
Planning for September 18th in Biscayne? Stay hydrated and seek shade during peak afternoon hours. Consider bringing rain gear or an umbrella.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 86°F | 78°F | 0.05" | -- |
| 2024 | 91°F | 79°F | 0.08" | -- |
| 2023 | 91°F | 78°F | 4.88" | -- |
| 2022 | 92°F | 76°F | 1.57" | -- |
| 2021 | 88°F | 74°F | 0" | -- |
| 2020 | 88°F | 81°F | 0" | -- |
| 2019 | 89°F | 76°F | 0.56" | -- |
| 2018 | 90°F | 78°F | 0" | -- |
| 2017 | 88°F | 77°F | 0" | -- |
| 2016 | 88°F | 80°F | 0" | -- |
| 2015 | 84°F | 73°F | 4.06" | -- |
| 2014 | 88°F | 74°F | 1.45" | -- |
| 2013 | 86°F | 79°F | 0.13" | -- |
| 2012 | 87°F | 78°F | 0" | -- |
| 2011 | 88°F | 75°F | 0" | -- |
| 2010 | 88°F | 81°F | 0" | 0" |
| 2009 | 88°F | 82°F | 0" | 0" |
| 2008 | 88°F | 77°F | 0" | -- |
| 2007 | 87°F | 78°F | 0.08" | -- |
| 2006 | 88°F | 80°F | 0" | 0" |
| 2005 | 89°F | 77°F | 0.03" | 0" |
| 2004 | 87°F | 78°F | 0" | 0" |
| 2003 | 87°F | 75°F | 0" | 0" |
| 2002 | 89°F | 76°F | 0.51" | 0" |
| 2001 | 87°F | 77°F | 0.58" | 0" |
| 2000 | 88°F | 74°F | 1.14" | 0" |
| 1999 | 86°F | 76°F | 0.58" | 0" |
| 1998 | 85°F | 72°F | 3.81" | 0" |
| 1997 | 86°F | 78°F | 0" | 0" |
| 1996 | 91°F | 81°F | 0" | 0" |
| 1995 | 93°F | 81°F | 0" | 0" |
| 1994 | 89°F | 81°F | 0" | 0" |
| 1993 | 86°F | 81°F | 0" | 0" |
| 1992 | 84°F | 75°F | 0.13" | 0" |
| 1991 | 88°F | 81°F | 0" | 0" |
| 1990 | 87°F | 78°F | 0" | 0" |
| 1989 | 88°F | 71°F | 1.8" | 0" |
| 1988 | 86°F | 76°F | 0" | 0" |
| 1987 | 87°F | 80°F | 0" | 0" |
| 1986 | 86°F | 80°F | 0" | 0" |
| 1985 | 79°F | 67°F | 7.32" | 0" |
| 1984 | 83°F | 76°F | 0" | 0" |
| 1983 | 87°F | 76°F | 0.66" | 0" |
| 1982 | 86°F | 79°F | 0" | 0" |
| 1981 | 87°F | 78°F | 0.23" | 0" |
| 1980 | 85°F | 80°F | 0" | 0" |
| 1979 | 85°F | 76°F | 0.58" | 0" |
| 1978 | 85°F | 80°F | 0" | 0" |
| 1977 | 85°F | 75°F | 0.28" | 0" |
| 1976 | 86°F | 78°F | 0.05" | 0" |
| 1975 | 85°F | 72°F | 1.07" | 0" |
| 1974 | 86°F | 80°F | 0" | 0" |
| 1973 | 87°F | 75°F | 0" | 0" |
| 1972 | 87°F | 80°F | 0" | 0" |
| 1971 | 87°F | 80°F | 0" | 0" |