Severe weather forecasters can predict severe weather that might form tornadoes a few days before the severe weather might hit an area. Forecasters can do this by looking at information, sent by the GOES satellite, about the pattern of winds and moisture that are approaching. Most major weather systems in the Northern Hemisphere move from the west to the east, but some move from the southeastern directions too.

Four things must be present in the atmosphere in order for thunderstorms to produce tornadoes. Those four things are; enough moisture, instability in the atmosphere, winds lifting from the ground, wind shear from the sky. Even if these conditions are present, that does not mean that a tornado will form. Tornadoes are very hard to predict because of this. The same weather pattern and situation that forms a tornado one day, might not form one on another day.