Weather on August 21 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
August 21st in Great Sand Dunes National Park (via Alamosa, CO) typically brings warm summer weather, with average highs around 80°F and lows near 45°F — a 35°F daily swing. Over 55 years of records, the warmest August 21st was in 2020 (70°F average), while the coldest was 2022 (51°F) — a 19°F range across recorded history. Rain or other precipitation has occurred on about 36% of August 21st dates historically, with the wettest August 21st recording 1.98" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for August 21st in Great Sand Dunes? 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 | 89°F | 46°F | 0" | 0" |
| 2024 | 87°F | 50°F | 1.09" | 0" |
| 2023 | 86°F | 43°F | 0" | 0" |
| 2022 | 63°F | 40°F | 0.08" | 0" |
| 2021 | 79°F | 41°F | 0" | 0" |
| 2020 | 91°F | 48°F | 0.03" | 0" |
| 2019 | 85°F | 46°F | 0" | 0" |
| 2018 | 82°F | 49°F | 0" | 0" |
| 2017 | 81°F | 46°F | 0" | 0" |
| 2016 | 73°F | 46°F | 0.03" | 0" |
| 2015 | 84°F | 42°F | 0" | 0" |
| 2014 | 81°F | 44°F | 0" | 0" |
| 2013 | 86°F | 44°F | 0" | 0" |
| 2012 | 67°F | 45°F | 0.33" | -- |
| 2011 | 83°F | 53°F | 0" | -- |
| 2010 | 81°F | 41°F | 0" | 0" |
| 2009 | 83°F | 42°F | 0" | 0" |
| 2008 | 79°F | 37°F | 0" | 0" |
| 2007 | 84°F | 41°F | 0" | 0" |
| 2006 | 72°F | 42°F | 0" | 0" |
| 2005 | 79°F | 44°F | 0" | 0" |
| 2004 | 74°F | 45°F | 0.15" | 0" |
| 2003 | 87°F | 48°F | 0" | 0" |
| 2002 | 78°F | 47°F | 0.03" | 0" |
| 2001 | 78°F | 47°F | 1.98" | 0" |
| 2000 | 82°F | 43°F | 0.99" | 0" |
| 1999 | 77°F | 49°F | 0.15" | 0" |
| 1998 | 78°F | 51°F | 0" | 0" |
| 1997 | 79°F | 46°F | 0.03" | 0" |
| 1996 | 76°F | 52°F | 0.08" | 0" |
| 1995 | 81°F | 46°F | 0" | 0" |
| 1994 | 76°F | 44°F | 0" | 0" |
| 1993 | 72°F | 51°F | 0.76" | 0" |
| 1992 | 83°F | 42°F | 0" | 0" |
| 1991 | 86°F | 41°F | 0" | 0" |
| 1990 | 75°F | 47°F | 0" | 0" |
| 1989 | 79°F | 39°F | 0" | 0" |
| 1988 | 85°F | 49°F | 0" | 0" |
| 1987 | 83°F | 51°F | 0.03" | 0" |
| 1986 | 86°F | 50°F | 0.1" | 0" |
| 1985 | 80°F | 45°F | 0" | 0" |
| 1984 | 79°F | 48°F | 0" | 0" |
| 1983 | 82°F | 42°F | 0" | 0" |
| 1982 | 80°F | 52°F | 0" | 0" |
| 1981 | 83°F | 47°F | 0" | 0" |
| 1980 | 82°F | 32°F | 0" | 0" |
| 1979 | 74°F | 34°F | 0" | 0" |
| 1978 | 82°F | 45°F | 0.03" | 0" |
| 1977 | 77°F | 43°F | 0.05" | 0" |
| 1976 | 80°F | 43°F | 0.08" | 0" |
| 1975 | 74°F | 50°F | 0.51" | 0" |
| 1974 | 80°F | 36°F | 0" | 0" |
| 1973 | 75°F | 50°F | 0.13" | 0" |
| 1972 | 78°F | 44°F | 0" | 0" |
| 1971 | 77°F | 49°F | 0" | 0" |