Landfall is when a tropical cyclone or waterspout moves from being over water to being over land. When a tornadic waterspout makes landfall it can be called a tornado, and can cause damage to buildings and other things made by people. When a fair weather waterspout makes landfall it quickly spreads out and loses its energy; the water falls as rain.
A tropical cyclone is said to make landfall when its center moves over land; in tropical cyclones this can be when the eye moves over land. This is where most of the damage occurs because when the storm is over water there is a little chance of damage, except if the parts of the storm that are raining are over land, which can cause severe flooding especially when the system is moving slowly or not at all. The effects of landfall are:
- the storm surge peaks
- the core of strong winds comes on shore
- and heavy flooding rains move over land.
Together with the high surf, these can cause a lot of beach erosion. In low lying areas the storm surge can stay inland for a long time and mix with chemicals already in the area to create a toxic mess. When a tropical cyclone makes landfall, the eye "closes", surf gets less, and winds get less as the cyclone spreads out, losing energy. Damage inland may include flooding rains, gusty winds, and severe weather associated with the cyclone's remnant thunderstorms.
A "landfall" should not be confused with a "direct hit", which happens when the core of high winds (or eyewall) comes over the land but the center of the storm stays over water. The effects of this are similar but storm surges can be much less. These effects are:
- high surf
- heavy flooding rains
- water building up along the coast
- minor storm surges
- beach erosion
- high winds
- possibly severe weather.