Medano Creek at 2023 peak flow on May 26. After a dry winter, late May snow on the mountains boosted snowpack to average levels, resulting in an average peak flow.
The creek may continue to gently flow at about 1 inch (2 cm) deepalong the eastern edge of the dunefield, near Castle Creek Picnic Area. Castle Creek is accessible by high clearance 4WD vehicle on the Medano Pass Primitive Road. Visitors without 4WD may also access the creek in late summer by hiking about 3 miles (5 km) up the creekbed from the Dunes Parking Lot, or 1.5 miles (2.5 km) from the Point of No Return parking area.
Conditions to Expect Each Month in an Average Year
While April is the second snowiest month of the year on average, there can also be warmer, sunny days that begin to melt the snowpack. Medano Creek usually arrives at the Dunes Parking Area sometime in April, at first just a trickle. By the end of April, it may be a few inches/cm deep with minimal surge flow.
Flow increases through May, and late May is near the peak of Medano Creek's annual flow. While it is still springtime and winds may arise, especially in the afternoon, May temperatures are generally moderate, with highs in the 60s-70s F. However, snow is still possible at this elevation in May! Trees and bushes along the creek leaf out. There are some "no-see-ums" (tiny biting gnats), but mosquitoes are rarely out in May. Late May and early June are the best opportunity to experience ‘surge flow’, where waves flow down across the sand. In average or wetter years, surge flow waves may be high enough for children to float down limited distances on flat inflatable toys. Water comes out of the mountains cold, but warms up significantly when the sun shines on it for a few hours as it spreads across the sand. Because of the creek's popularity, late May and early June weekends are extremely crowded, with long lines of traffic, overflowing parking lots, a crowded beach, and full campgrounds. If possible, plan your visit on a weekday this time of year.
June brings warmer temperatures for water play and generally pleasant conditions the first week of June. Late May and early June are the best opportunity to experience "surge flow", where waves flow down across the sand. In average or wetter years, surge flow waves may be high enough for children to float down limited distances on flat inflatable toys. As the creek becomes much lower around mid-June, mosquitoes emerge in large numbers. Move away from vegetation, to the far side of the creek to avoid the worst of the mosquitoes: they don't like open sand, but prefer to be near shady bushes and trees. By late June, the water level will be fairly low, only 1 or 2 inches (1-5cm) or may even be drying up. Because of the creek's popularity, late May and early June weekends are extremely crowded, with long lines of traffic, overflowing parking lots, a crowded beach, and full campgrounds. If possible, plan your visit on a weekday this time of year.
In July, unless there are significant ongoing rains, the creek will be retreating back toward the mountains and will be dried up at the main visitor area near the Dunes Parking Lot. It may continue to gently flow at at 1-2 inches deep (2-5 cm) along the eastern edge of the dunefield, near the Castle Creek Picnic Area. Castle Creek is accessible by high clearance 4WD vehicle on the Medano Pass Primitive Road. Visitors without 4WD may also access the creek in late summer by hiking 1-3 miles (3-5 km) up the creekbed from the Dunes Parking Lot, or 0.7-1.5 miles (1-2.5 km) from the Point of No Return parking area. Mosquitoes are typically still present in large numbers around the low, warm water the first 2-3 weeks of July, but begin to disappear as the water continues to retreat farther back toward the mountains. July is the warmest month at the park, with average highs in the low 80s F.
In August and September, the creek is still completely gone from the main visitor area near the Dunes Parking Lot. It may continue to gently flow at at 1-2 inches deep (2-5 cm) along the eastern edge of the dunefield, near the Castle Creek Picnic Area. Castle Creek is accessible by high clearance 4WD vehicle on the Medano Pass Primitive Road. Visitors without 4WD may also access the creek in late summer by hiking 1-3 miles (3-5 km) up the creekbed from the Dunes Parking Lot, or 0.7-1.5 miles (1-2.5 km) from the Point of No Return parking area. Mosquitoes are typically gone in August and September.
Click on the chart image for up-to-the-minute flow in Medano Creek.
NRCS
Check Up-To-The-Minute Flow
See the current flow and trend of Medano Creek as a graph.
(Available spring through fall). The creek's flow on this graph is measured where it emerges from the forest and first enters the dunefield, not where it spreads out across the sand 5 miles downstream. This measurement gives an indication of the current flow relative to average peak flow. Peak flow in an average year is 40 cubic feet per second (cfs), typically occurring in late May or early June. When flow drops below 4 cfs, Medano Creek does not usually reach the Dunes Parking Area.
Médano is a Spanish word that means "sand dune". It is pronounced "MED-ah-no". In the original Spanish there is an accent on the é.
Two skimboarders try their sport on Medano Creek.
Photo courtesy Nathan Salley. Used by permission.
Medano Creek Activities
Depending on water level, visitors may do any non-motorized and non-mechanized activities in the creek, including splashing, surfing, wading, skimboarding, floating (works only in small raft or tube with a child at peak runoff), sand castle building, and sand sculpting.
To protect this riparian habitat, please do not disturb living plants or animals, and keep water resources clean.
Last updated: August 23, 2023
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Contact Info
Mailing Address:
Visitor Center
11999 State Highway 150
Mosca,
CO
81146
Phone:
719 378-6395
Great Sand Dunes Visitor Center main number
