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DISCOVERY
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Hurricane tracking and predicting today is really very complicated. Fortunately, the National Hurricane Center (NHC) in Miami, Florida is responsible for the more complicated kind of hurricane forecasting. The NHC starts tracking a tropical storm when it reaches the tropical depression stage--a storm with some rotary motion but with winds of 38 mph or less. They follow it until it grows to hurricane status or until it dies out.
To forecast the path and intensity of a storm, NHC uses computer models. These models complicated computer programs, but not nearly as complicated as nature. However they are much more complicated than the technique that you are using in Hurricane Activity # 1.
Meteorologists use more than one model to track and predict hurricane movement. This is a problem because when the computers make their predictions the models are often different from each other. This is an advantage because each type of model has its own particular strengths. Human hurricane forecasters have to interpret the results from the different models to arrive at the track and intensity forecast that will be broadcast to the public.
Three different computer models are used by NHC: statistical, dynamical, or combination (statistical and dynamical together). Statistical models use current information about the hurricane and compare it to historical data about the behavior of similar storms. The historical record for storms over the north Atlantic begins in 1871, but the record for the east Pacific only goes back to 1945.
Dynamical models work differently. To make a forecast, they combine computer simulations of the atmosphere with inputs of current wind, temperature, pressure, and humidity conditions. Dynamical models ignore historical storms. Combination models use the strengths of both models.
Today, the dynamical models are winning the race for accuracy. These models are especially good when hurricanes come close to the continents where the atmospheric environment is well-known and understood. But over the oceans, far removed from land, combination models are still the best performers.