This time of year, you will sometimes hear meteorologists talk about left moving and right moving thunderstorms. Here is an example and I will then explain why it is important.
Typically, the left mover will cause large hail and the right mover will produce a tornado.
Second Image of Splitting Thunderstorm
Like everything in meteorology, this does not work 100% of the time, but it is something to keep in mind during the rest of storm season.