Forecasting where a hurricane is going to hit is hard! Often, large areas of the coast are evacuated before a hurricane lands because forecasters aren't exactly sure which places are really in the most danger. This means that many times people are evacuated from areas that aren't affected by the hurricane. This is frustrating for both the people who have to leave their homes and the weather forecasters who would like to produce an accurate forecast every time. Over the years, forecasts have improved as scientists learn more about hurricanes, but they still aren't perfect.
Why is that true? Why is it so difficult to predict where and when a hurricane will land and how strong it will be? The main reason is that tropical cyclones, like all other weather systems, are pushed by motions that are taking place throughout the depth of the atmosphere and are constantly changing.
Those changes in the atmosphere are very complicated, and it's not possible for computer models to simulate them perfectly. The simple exercise we're going to do here will show how some fairly small changes can make a big difference in where a hurricane makes landfall. The examples here are based on actual hurricane model predictions.
We'll start with a hurricane that forms at 15° north latitude and 50° west longitude. This is in the Atlantic Ocean and a little north of eastern South America.
