Grand Marais MN Monthly Weather Forecast weathercomClimate within the heart of Grand Marais, Minnesota is always changing. Whether it's bright or overcast, you can expect an array of weather conditions throughout the year. Starting from the beautiful springtime flowers blossoming to the hot and sun-soaked summer days, to the colorful autumn foliage, and the snowy landscapes during winter, Grand Marais, Minnesota provides a wide selection of climate experiences all through the year.