Grand Marais MN Monthly Weather Forecast weathercomAtmospheric conditions at Grand Marais, Minnesota is perpetually changing. Whether bright or overcast, look forward to a selection of climate patterns during the year. Beginning in the stunning springtime flowers blossoming to the hot and sun-soaked summer days, to the colorful fall foliage, and the snowy landscapes during winter, Grand Marais, Minnesota offers a wide range of climate experiences throughout the year.