The greatest number of tornadoes worldwide occur in the United States. Tornadoes occur frequently in Missouri, Arkansas, Kansas, Oklahoma, Texas, Tennessee, and Mississippi. They are a bit less frequent in the northern plains states and Ohio Valley. Every state in the USA has had tornadoes at some time.
Since tornadoes are a form of weather they would be studied mostly by meteorologists. Some of these may be storm chasers, who conduct research in the field with tornadoes as they occur, though most storm chasers are not scientists.
Hail and tornadoes are most often associated with cold fronts, but can occur with dry lines or, lest often, warm fronts.
Severe thunderstorms most often occur ahead of cold fronts.
Tornadoes can occur any time of the year, but are most likely in the months of April through June. Spotters would most likely be able to see a tornado in an open area, with an unobstructed view. Most tornadoes occur between the hours of 4 and 9 PM, but can occur at any time of the day.
"Fire tornadoes," more properly called firewhirls, are most common in states prone to intense wildfires. Statistical data is not available, but California would likely be a good candidate.
Tornadoes can occur in Maryland, but they are relatively rare compared to other states in the tornado alley region. Maryland experiences an average of around 10 tornadoes per year, with the peak tornado season typically occurring in late spring and early summer. It's important for residents to stay informed about weather alerts and have a plan in place in case a tornado does occur.
Tornadoes are likely to be rare near the equator due to the lack of organized weather systems. Those that would occur would probably be weak and cloud likely be found spinning clockwise or counterclockwise in equal numbers. Unlike large-scale systems such as hurricanes, tornadoes to not get their rotation from the Coriolis effect, but rather from local or regional wind shear.
Fire tornadoes, more properly called firewhirls, can occur in any area prone to major fires.This would include most of the Southwestern United States.
Tornadoes can occur in any part of North Carolina, but the central and eastern regions of the state, including areas like the Piedmont and Coastal Plain, are more prone to experiencing tornadoes due to favorable atmospheric conditions. Tornadoes can also occur in the western part of the state, particularly in the Appalachian Mountains foothills.
Hail and tornadoes would most likely be associated with a cold front or dry line.
Tornadoes do not come to life as they are not alive. As to, who, the answer would depend on your religious standpoint. Most scientists would say that nobody creates tornadoes; they are just a consequence of interactions of air currents in a thunderstorm. A Christian would likely say that God creates tornadoes.
I don't believe tornadoes occur over water. Maybe a better question would be "How do hurricanes effect Coral Reefs".