When the air is colder than the air ahead of it, the front is called a Cold Occlusion . When the air behind the front is milder than the air ahead of it, it is called a Warm Occlusion. These processes lead to the dissipation of the front in which there is no gradient in temperature and moisture.
Offshore flow occurs when air moves from land to sea.
It is usually associated with dry weather. Meanwhile onshore flow is when air over the water advances across land. It usually indicates an increase in moisture. This National Weather Service marine forecast is designed to serve users who operate beyond the coastal waters where it usually requires more than a day or more of sailing to and from port. These users are mainly commercial fishermen and merchant shipping and, to a lessor extent, government and research vessels and large recreational craft.