We were just there last weekend and Medano Creek was running pretty good with plenty of snow on the mountain peaks. The Creek will probably run till June. The sand was great!
When the Snow Melts.... From Great Sand Dunes National Park: Forecast Flow for 2019 Season Snowpack in Medano Pass is currently 160% of average for this date. Medano Creek's flow is now forecast to be over 150% of average in depth and duration in 2019. See below for what to expect of Medano Creek month by month in an average year. April is typically the second snowiest month of the year, so final snowpack totals will depend on weather conditions in the 2 weeks. Dry, windy conditions can reduce snowpack, while snowy conditions will maintain or increase it.
I think it's April or early May depending on how cold it stays.
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