The best season for viewing the sea of clouds on Mount Huangshan is from winter to spring. Mount Huangshan has an average of 255.9 fog days per year, and November to May is the best time to view the Sea of Clouds on Mount Huangshan, especially after rain and snow, before sunrise and sunset, the Sea of Clouds must be the most spectacular. Sea of clouds is one of the most important landscapes in mountain scenery. The so-called sea of clouds, refers to the formation of clouds in certain weather conditions, and the height of the top of the clouds is lower than the height of the summit, when people at the top of the mountain when looking down on the clouds, see the boundless clouds, such as the coast of the sea, the wave peaks surging, waves splashing, waves lapping at the shore. Therefore, this phenomenon is called "sea of clouds". Mount Huangshan 365 days a year only 51 days can see the sea of clouds. Huangshan annual average of 62 days of fog, 35.9 days of freezing rain. Most of Mount Huangshan is freezing fog in the form of grains, which is easy to form when the temperature is -2 to -7℃. Freezing rain can form when the fog droplets expand to a gross level. Mount Huangshan has a complex topography and obvious differences in microclimate, so there are places with more freezing rain and places with more freezing fog, and sometimes both can appear at the same time. The reasons for the formation of the sea of clouds and the law: Huangshan mountain valley low, lush forests, short sunshine hours, water is not easy to evaporate, and thus high humidity, more water. After the rain common wisps of light fog, rising from the valley. The average annual fog day 250 days or so, can be called the home of the clouds. Huangshan sea of clouds is formed by low clouds (cloud bottom height below 2500 meters) and ground fog. Low clouds are mainly stratocumulus, which is its characteristics. Mount Huangshan every year from November to March, 97% of the sea of clouds formed by stratocumulus clouds, only 3% by the formation of layer clouds or fog. 6 to September, there are light cumulus clouds and thick cumulus clouds formed by the sea of clouds, accounting for about 6% of the total number of clouds in the period.