What is the weather like in the Rocky Mountains?
It is often very cold, so don't go in summer clothes. There is normally snow near the top.
Indeed they are. Misconceptions rise about the same geographic features. Like most names, the Rocky mountains was shortened to the Rockies because people were too lazy to just say Rocky mountains and instead said the Rockies, which leads to misconceptions like this. Similarly, the Canadian Rockies seems to be the preferred term in the US rather than "Canadian Rocky Mountains."