Yes. Friction is always a factor. It is partly through drag, which can be thought of as friction, that the wind in a tornado is able to cause damage.
Tornadoes typically weaken when they lose their source of warm, moist air that fuels their intensity. This can happen when a tornado moves into a cooler or drier environment, or when the storm system that spawned the tornado weakens. Tornadoes can also weaken as they interact with friction from the earth's surface or from encountering other weather phenomena.
Lightning occurs within tornadoes due to intense convective forces and the separation of electrical charges within the storm. As air rises rapidly inside the tornado, friction between particles can create and build up static electricity, leading to lightning discharges.
Tornadoes lose their power when they encounter friction and drag with the Earth's surface, or when they move into an environment with less warm, moist air to fuel their strength. Additionally, interactions with other weather systems can disrupt the organization of the tornado, causing it to dissipate.
Tornadoes generally form on flat terrain, but they can move up or down elevation changes such as hills. However, tornadoes are more likely to dissipate or weaken as they move over higher elevations due to friction and other factors that disrupt their circulation.
Largely by coincidence, the most tornado-prone area in the world, the Great Plains is also a very flat area. However, the hills of Tennessee and northern Alabama are also quite prone to tornadoes.
Tornadoes in the U.S. are called tornadoes.
Gravity, electromagnetism, friction, and wind are forces that occur in nature. Earthquakes, volcanic eruptions, lightning, and tornadoes are natural phenomena that occur in nature.
Tornadoes are sometimes divided into "weak" tornadoes "strong" and "violent" tornadoes. Weak tornadoes are those rated EF0 and EF1. Most tornadoes are weak. Strong tornadoes are those rated EF2 and EF3. Violent tornadoes are those rated EF4 and EF5. They are the rarest of tornadoes, only about 1% of tornadoes are this strong.
Tornado do happen near and on the coast. It just so happens that the areas that get strong tornadoes (the tornadoes that get all the attention) happen to be inland. The strong thunderstorms that produce most tornadoes form most easily when warm, moist air collides with cool and/or dry air along with a few other conditions. These meet most ideally in inland areas but tornado outbreak along coasts have also ocurred.
It depends on what you mean by extreme. Tornadoes of EF4 and EF5 tornadoes, however are often referred to as violent tornadoes. These account for about 1% of all tornadoes.
Hills and mountains can, to some degree, disrupt thunderstorms from organizing, making tornadoes less likely. Overall, through, tornadoes are more influenced by climate than topography. It just so happens that the most tornado-prone region in the world, the central U.S., is also quite flat.
Tornadoes don't get named, Hurricanes do, but Tornadoes don't.