Severe Weather in El Salvador

The formation of a Tornado is rather simple with the right conditions. The first necessary condition is wind sheer to create a stronger wind aloft while the wind on the ground moves more slowly. This creates a tumbling effect that grows strong because of the wind sheer and friction. This horizontal rotation of air next needs to meet an updraft to be brought to create the vertical mesocyclone. Next the mesocyclone develops in the updraft of a thunderstorm until it descends to the ground forming a tornado.

In the United States, tornadoes usually travel with the westerlies from the South West to the North East across tornado alley. On average year, El Salvador doesn't experience any tornadoes on an average year which is quite the opposite of the US which experiences the most of any region in the world with an average of 1253 tornadoes per year. (http://www.ncdc.noaa.gov/climate-information/extreme-events/us-tornado-climatology) Below is a map of all the tornado hot spots in the world and as you can clearly see, El Salvador is very far from any of these regions. And below that is a graph of tornado count since the 50s, but it may be swayed because of advancements in technology as well as population growth have made it increasing more likely that a tornado will now be documented.
Another type of natural disaster that is slightly more prevalent in El Salvador is hurricanes. Because warm ocean waters, deep ocean layers, and the Coriolis effect are needed to form a hurricane, they form in the tropics and head east until they gain strength and head north when they reach landfall. In the United States, hurricanes generally hit the south and south east after being generated in the lower latitude tropics. These also form in other parts of the world under different names like cyclone in the Indian ocean and typhoon in the western pacific. Hurricanes are much larger and can cause more damage then tornadoes, so it is lucky that on average only 1.72 hit the US each year (http://www.aoml.noaa.gov/hrd/tcfaq/E17.html) but El Salvador's location near the equator and the land blocking it to east from the Caribbean make it experience even less hurricanes averaging 0 per year.