CHARLOTTE, NC (WBTV) - NASA has just released it's first Global Rainfall and Snowfall map. You'll enjoy this, go here and hit the play button: http://1.usa.gov/1axLkSe
You're watching a time lapse of storms crossing the planet Earth. A couple things to note - watch how the storms move from west to east both in the northern and southern hemisphere. Yet, all the action around the tropics is moving from east to west, the opposite direction. The rotation of the earth is the primary influence for the mid-latitude jet streams blowing from west to east and carrying those storms along with them.