July is by far the most popular month, combining the Moldejazz festival with the best summer weather and the longest days. Accommodation fills up during festival week and should be booked months in advance. Outside the festival, July and August are pleasant and relatively dry by Norwegian west coast standards, though rain is possible at any time.
May, June, and September offer good weather without the crowds, and late May has the advantage of snow still covering the mountain peaks while the fjord is fully accessible. Winter (November through March) is dark, rainy, and cold — not a traditional tourist season, though the town functions normally and the Romsdal Museum remains open.