Grand Marais MN Hourly Weather Weather in the heart of Grand Marais, Minnesota is constantly shifting. Whether bright or cloudy, look forward to a range of weather patterns throughout the year. Beginning in the breathtaking spring flowers blossoming to the warm and sun-filled summertime days, to the colorful autumn foliage, and the snow-covered landscapes during winter, Grand Marais, Minnesota presents a varied range of climate experiences during the year.