Climate Grand Marais Minnesota and Weather averages Grand Atmospheric conditions inside Grand Marais, Minnesota is consistently shifting. No matter if it's bright or cloudy, you can expect a range of climate patterns over the year. Beginning in the beautiful springtime flowers blooming to the hot and sun-soaked summertime days, to the scenic fall foliage, and the snow-covered landscapes during winter, Grand Marais, Minnesota presents a diverse range of climate experiences throughout the year.