Weather on September 18 in Santiago
Historical weather data for September 18 in Santiago, Chile
Avg High21°C (69°F)
Avg Low6°C (43°F)
Warmest202522°C
Coldest19908°C
Based on 49 years of data from QUINTA NORMAL
About This Date
September 18th in Santiago, Chile typically brings mild fall weather, with average highs around 21°C and lows near 6°C — a 26°F daily swing. Over 49 years of records, the warmest September 18th was in 2025 (22°C average), while the coldest was 1990 (8°C) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 12% of September 18th dates historically, with the wettest September 18th recording 5.11" of rain.
Planning for September 18th in Santiago? Great weather for outdoor activities.
Year by Year History
| Year | High | Low | Precip |
|---|---|---|---|
| 2025 | 29°C (85°F) | 16°C (60°F) | -- |
| 2024 | -- | 8°C (46°F) | 0" |
| 2023 | -- | 7°C (44°F) | 0" |
| 2022 | 25°C (77°F) | 7°C (45°F) | -- |
| 2021 | -- | 6°C (43°F) | 0" |
| 2020 | 27°C (81°F) | 7°C (44°F) | 0" |
| 2019 | -- | 4°C (39°F) | 0" |
| 2018 | -- | 10°C (50°F) | 1.14" |
| 2017 | 26°C (78°F) | 7°C (45°F) | 0" |
| 2015 | 19°C (67°F) | 6°C (42°F) | 0" |
| 2014 | -- | 8°C (46°F) | 0" |
| 2013 | -- | -1°C (30°F) | 0" |
| 2012 | 15°C (59°F) | 7°C (45°F) | 0" |
| 2011 | 22°C (71°F) | -- | -- |
| 2009 | -- | 7°C (44°F) | 0" |
| 2008 | -- | 12°C (53°F) | 0" |
| 2007 | -- | 2°C (35°F) | -- |
| 2006 | 28°C (82°F) | 9°C (48°F) | -- |
| 2005 | -- | 4°C (40°F) | -- |
| 2004 | 18°C (64°F) | -- | -- |
| 2003 | 23°C (73°F) | 9°C (48°F) | 0" |
| 2001 | 18°C (64°F) | 4°C (40°F) | 0" |
| 2000 | -- | 7°C (45°F) | -- |
| 1999 | 21°C (69°F) | 8°C (46°F) | -- |
| 1998 | -- | 8°C (47°F) | 0" |
| 1997 | 29°C (84°F) | 11°C (51°F) | 0" |
| 1996 | -- | 10°C (50°F) | 0.1" |
| 1995 | 18°C (64°F) | 6°C (42°F) | 0.05" |
| 1994 | 23°C (73°F) | -- | 0" |
| 1993 | -- | 4°C (39°F) | 0" |
| 1992 | 17°C (62°F) | 2°C (35°F) | 0" |
| 1991 | -- | 3°C (38°F) | 0" |
| 1990 | 16°C (60°F) | 1°C (33°F) | -- |
| 1989 | -- | 8°C (46°F) | 0" |
| 1988 | 17°C (63°F) | 3°C (37°F) | 0" |
| 1987 | 22°C (71°F) | 4°C (40°F) | 0" |
| 1986 | 18°C (64°F) | 1°C (33°F) | 0" |
| 1984 | -- | 8°C (46°F) | 0.1" |
| 1983 | -- | 3°C (37°F) | 1.09" |
| 1982 | 17°C (62°F) | -- | -- |
| 1981 | 20°C (68°F) | 4°C (39°F) | 0" |
| 1980 | 13°C (55°F) | 7°C (45°F) | 0" |
| 1979 | -- | 1°C (34°F) | 0" |
| 1978 | -- | 1°C (34°F) | 0" |
| 1977 | 20°C (68°F) | 7°C (45°F) | 0" |
| 1976 | 27°C (81°F) | 5°C (41°F) | -- |
| 1975 | -- | 11°C (52°F) | -- |
| 1974 | -- | 4°C (39°F) | 0" |
| 1973 | 15°C (59°F) | 3°C (37°F) | 5.11" |