To understand how storms work and to anticipate their behavior, meteorologists turned to a new forecasting tool in recent years: powerful supercomputers that create sophisticated virtual models of hurricane seasons. Before the summer hurricane season begins, scientists at the National Oceanic and Atmospheric Administration (NOAA) now amass a vast amount of data from weather satellites and input it into a supercomputer at the Climate Prediction Center in Gaithersburg, Md. A sophisticated computer program then simulates the interaction of the atmosphere and ocean in an effort to predict when storms will emerge, how big they will be, and how they will behave [source: Strickland].
Government weather forecasters are so convinced of the value of such modeling that they recently upgraded their supercomputers to be able to perform an astonishing 213 trillion calculations per second (about 200,000 times the speed of an iPad), and store 2,000 terabytes of data -- roughly the equivalent of 2 billion digital photos. All that power has already improved the accuracy of their weather forecasting by 15 percent. The result is that people in hurricane-prone areas get a little more lead time to make preparations and evacuate.
As National Weather Service official Andy Nash explained in a 2013 interview, "Instead of maybe three days out knowing where [Hurricane] Irene was going to go, maybe its three-and-a-half to four days" [source: Borelli].