What Makes Colorado Wine Unique

BookCliff at Vina Cobos in Mendoza

It sounds boring, but the answer is what is in the soil and the climate, in other words the famous terroir. Colorado's Grand Valley AVA has its unique terroir, located in the former riverbed of the Colorado river characterized by a continental, arid climate and high elevation. During the summer and fall it is typical to experience high temperature swings between the daytime high and the nighttime low.
The higher elevation creates grapes with a thicker skin, especially noticeable in red grapes. The low night temperatures preserve the acidity in the fruit. The result is wine with some grit, more structure, tannins especially when young and higher acidity expressed in a crisp finish. All of this contributes to wine that ages well in the bottle and cellar. And can complement food very well.
I had to visit Argentina and specifically Mendoza to get a better understanding what makes Colorado wine taste different from Californian wine. Mendoza has a similar climate and soil as Colorado's grape country, high dessert, arid climate and similar soil. The highest elevation vineyards in Mendoza (Uco valley) are 4,900 feet, Palisade, CO is at 4,600 feet. All vineyards are irrigated in Mendoza, just as in Palisade. No wonder the red wines from Mendoza and Colorado taste similar.