Weather on December 18 at Great Sand Dunes
Great Sand Dunes National Park and Preserve
Based on 55 years of data from Alamosa, CO
Elevation Note: Great Sand Dunes sits at 8,200 ft. Expect temperatures 29°F cooler than the data shown below, which comes from Alamosa, CO at a lower elevation.
Planning Your Visit
December 18th in Great Sand Dunes National Park (via Alamosa, CO) typically brings cold winter weather, with average highs around 35°F and lows near -1°F — a 36°F daily swing. Over 55 years of records, the warmest December 18th was in 2025 (33°F average), while the coldest was 1996 (0°F) — a 33°F range across recorded history. Precipitation has occurred on 15% of recorded December 18th dates, with snow falling 15% of the time (heaviest snowfall: 1.4"). The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
Planning for December 18th in Great Sand Dunes? Bundle up with warm layers and protect extremities from the cold.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 55°F | 10°F | 0" | -- |
| 2024 | 48°F | 9°F | 0" | 0" |
| 2023 | 36°F | -4°F | 0" | 0" |
| 2022 | 30°F | -8°F | 0" | 0" |
| 2021 | 39°F | -5°F | 0" | 0" |
| 2020 | 28°F | -5°F | 0" | 0" |
| 2019 | 21°F | -10°F | 0" | 0" |
| 2018 | 42°F | 6°F | 0" | 0" |
| 2017 | 45°F | 4°F | 0" | 0" |
| 2016 | 29°F | -2°F | 0.05" | 0.8" |
| 2015 | 30°F | -1°F | 0" | 0" |
| 2014 | 35°F | 13°F | 0.05" | 0.6" |
| 2013 | 34°F | -1°F | 0" | 0" |
| 2012 | 27°F | -9°F | 0" | 0" |
| 2011 | 29°F | -6°F | 0" | -- |
| 2010 | 30°F | 8°F | 0.03" | 0.1" |
| 2009 | 43°F | -2°F | 0" | 0" |
| 2008 | 37°F | 18°F | 0.03" | 0.3" |
| 2007 | 22°F | -15°F | 0" | 0" |
| 2006 | 42°F | 14°F | 0" | 0" |
| 2005 | 36°F | -5°F | 0" | 0" |
| 2004 | 44°F | 1°F | 0" | 0" |
| 2003 | 37°F | -2°F | 0" | 0" |
| 2002 | 32°F | 4°F | 0" | 0" |
| 2001 | 41°F | -2°F | 0" | 0" |
| 2000 | 27°F | -2°F | 0" | 0" |
| 1999 | 37°F | 1°F | 0" | 0" |
| 1998 | 51°F | 3°F | 0" | 0" |
| 1997 | 24°F | -6°F | 0" | 0" |
| 1996 | 19°F | -19°F | 0" | 0" |
| 1995 | 34°F | 2°F | 0" | 0" |
| 1994 | 39°F | 3°F | 0" | 0" |
| 1993 | 33°F | 0°F | 0" | 0" |
| 1992 | 30°F | -15°F | 0" | 0" |
| 1991 | 20°F | -16°F | 0.36" | 1.4" |
| 1990 | 21°F | -17°F | 0" | 0" |
| 1989 | 35°F | 2°F | 0" | 0" |
| 1988 | 39°F | -2°F | 0" | 0" |
| 1987 | 35°F | 19°F | 0.05" | 0.3" |
| 1986 | 34°F | 18°F | 0" | 0" |
| 1985 | 35°F | -5°F | 0" | 0" |
| 1984 | 40°F | -8°F | 0" | 0" |
| 1983 | 29°F | -1°F | 0" | 0" |
| 1982 | 44°F | 8°F | 0" | 0" |
| 1981 | 42°F | -4°F | 0" | 0" |
| 1980 | 53°F | 6°F | 0" | 0" |
| 1979 | 45°F | -5°F | 0" | 0" |
| 1978 | 38°F | 12°F | 0.05" | 0.2" |
| 1977 | 42°F | 6°F | 0" | 0" |
| 1976 | 32°F | -11°F | 0" | 0" |
| 1975 | 30°F | -8°F | 0" | 0" |
| 1974 | 34°F | 6°F | 0" | 0" |
| 1973 | 37°F | 1°F | 0.2" | 1.3" |
| 1972 | 33°F | -6°F | 0" | 0" |
| 1971 | 18°F | -16°F | 0" | 0" |