Types of Atmospheric Models

Low pressure winds attract moist air, forming tropical waves every three to four days in the Gulf of Mexico, Caribbean Sea, Pacific and Atlantic oceans. A Coriolis force increases the velocity of westerly winds, causing them to spiral counterclockwise around the Northern Hemisphere or clockwise in the Southern Hemisphere. The results are tropical depressions, thunderstorms and hurricanes.

Labeling Rapid-Intensity Storm Stages

Meteorologists currently describe four distinct stages of hurricanes, all typically classified as tropical cyclones or low-pressure systems with defined wind circulation. The first stage, tropical disturbance, can surge to tropical depression status, then grow into a tropical storm and fuel a full on hurricane, which may or may not have an eye wall. The eye wall is a donut-shaped area, surrounding the center or strongest wind area of the hurricane.

From Tropical Storm to Hurricane

Once a tropical cyclone turns into a tropical storm, it is given a name by the National Hurricane Center (NHC). Sustaining one-minute winds at 10-meter elevations of 34-63 knots, tropical storms swirl into hurricanes, based on the Saffir-Simpson 1-5 Scale that clocks barometric pressure, destructive potential and wind speeds of at least 10-meter elevations at 64 knots. For example, tropical storm Katrina suddenly appeared off the southeast Florida coast in 2005, then quickly transitioned into a hurricane as it traversed the Florida peninsula.

Best Atmospheric Models for Measuring Hurricanes

The most efficient forecasts combine three or more models to form a consensus forecast. NHC has achieved increasing accuracy using the average of various combinations of several traditional computer models: GFS, GFDL, ECMWF, HWRF, NOGAPS and UKMET. ECMWG has emerged as a top-performing model. GFS and GFDL have gained recognition as second and third place models with UKMET following close behind. New models, such as TCOA, TVCA and UMCM, promise an even higher level of computational power for predicting hurricanes.