Cottonwood Lake sits in Chaffee County, Colorado, west of Buena Vista in the San Isabel National Forest, at a recorded 2,920 metres — a shade under 9,600 feet. It is a small mountain lake held in a drainage rather than on an exposed plain, which makes it a useful contrast with Antero at a similar altitude.
What drives the score here
Cold water is the hazard that matters most here, and it is one the score cannot see. At close to 9,600 feet, water temperature lags air temperature by a wide margin for most of the paddling season, and no sensor measures it, so a day that looks ideal from the shore can score well over water that is still very cold. Its position in a drainage gives it more shelter than the open reservoirs, so wind is less often the deciding factor than elevation is. Of the Colorado spots here, Cottonwood is the one where the water, not the weather, is most often the real limit — dress for immersion even when the number looks good.
What the Paddle Score measures
A single number from 1 (Danger) to 5 (Excellent), built from wind speed and gusts, air temperature, UV index, cloud cover, precipitation and visibility at the lake — then constrained by fixed safety rules the model is not allowed to override. Wind above 25 mph costs two full points. Water temperature counts only where a sensor measures it, and none covers this lake yet, so judge cold water yourself. No score after dark, or while the lake is frozen or closed.
What the score can’t see
Small high-altitude lakes change character quickly when weather moves through the range, and a small surface responds faster than a large one. A three-day forecast is a weaker instrument here than it is at low elevation, and I would weight the near hours far more heavily than the far ones.
Wear a life jacket, every time. The Paddle Score is a decision aid, not clearance to go out. It cannot account for your skill, your equipment, currents, traffic, or hazards at your launch site.