How good is the month of December to visit Grand canyon?
I really like the Grand Canyon in winter. The crowds are much lower, room rates are cheaper, the temperatures are nice for hiking, and a little fresh snow can make the canyon look extra beautiful. It will be cold on the rim in December and so you will want to have warm clothes, especially at night. There is also a small chance of a snow storm hitting while you are there. A really heavy storm where there is lots of snow coming down and it too cold and miserable to be out even with warm clothes generally only happens about a half dozen times each winter (particularly given the recent drought) and generally clears up within a day or two. There will also be a few milder storms throughout the winter with cloudy skies and some blowing snow flakes, but these are not too bad. Of course, the above is just the average – some winters they get a lot more storms, other winters (especially recently) they get little to no snow the whole season. Note that while much of Arizona and southern Utah is des