A monsoon is a seasonal prevailing wind which lasts for several months. It is wind blowing part of the year from one direction, alternating with a wind from the opposite direction. The word monsoon is derived from the Arabic word mausim, which means “season” and refers to a wind system that reverse direction between winter and summer.
One of its kind is Hanging Habagat or Southwest Monsoon. It is a violent wind brought by typhoons of the tropics and comes from southwest direction and bring heavy rains in west part of the Philippines. The southwest monsoon is generally expected to begin around the start of May through October. In a report prepared by the Department of Science and Technology (DOST), this natural phenomenon gets its start during the summer months in the northern hemisphere, when the Asiatic continent becomes warmer than the surrounding seas so a low-pressure area develops over the continent. This happens when a large mass of air rises, causing low pressure in the area the mass left empty and inducing air from over the ocean to flow towards the continent. The winds, rushing toward the low-pressure area, carry heat and water vapor which, when passing across the Philippines, becomes the prevailing winds in the country. "This is what is locally known as the ‘habagat,’ the southwest monsoon," the report said. The report said it is the country’s western portion that receives a substantial amount of rainfall while the southwest monsoon holds sway over the Philippines.