The HURRICANE model simulates the heat and energy dynamics of a tropical cyclone, known in the Atlantic as a hurricane. Surface winds pick up heat and energy in the form of water vapor as they converge near the center of the storm. The air rises, cashing in its latent heat energy to blow out the top of the storm system, leaving prodigious rainfall and a low pressure core which pulls more air in, perpetuating the storm.

The model runs a 20-day transient simulation based on the conditions set up in the upper left part of the page. The page saves output from the run which can be replayed using the Replay button, or by changing one of the plot selections. A point in time in the simulation can be examined by dragging the Time Slider.

The colors indicate the azimuthal wind speed (going around in a circle), with redder colors showing faster winds according to the color scale on the right. The computational model works from the center, 0, out to 150, assuming that these conditions hold in all directions from the center. The model output was flipped and added to the left-hand side of the figure to better show the storm structure.

First watch the animation of the default simulation.

The pull-down menus above the plots give options of what plots to look at. Changing one of these plot options will trigger the animation to run again. There is also a Replay button which will repeat the animation using the plot options already selected, and a Time Slider which lets you roll back time to an earlier part of the simulation, to examine the plots without them changing.

The numerical values of the model output in the color field can be obtained by hovering the cursor over the field. It may take a second for your browser to dig up the value.

The plot on the lower left shows quantities as a function of time, with default setting Maximum Wind Speed This plot updates in time with the animation.

The lower right shows quantities as a function of the distance from the center of the storm, with default setting Surface Pressure.

The upper plot scales the color according to model values that span dimension of radius and height, such as the default Azimuthal Velocity. If you change one of the model run parameters in the upper left, a button will appear to Get New Run. It takes a few seconds to compute but when it's finished you'll be able to watch multiple animations the same way as for the initial simulation.

How important is the Sea Surface Temperature to the eventual strength of a hurricane? Measure strength as Maximum Surface Wind, or Surface Pressure, as a function of the SST.

When Ocean Mixing is enabled, how much colder does the oean surface get because of the hurricane (it's one of the radial plots in the lower right)? What happens to the strength of the hurricane?

Does a change in Temperature Aloft have the same impact on hurricane strength as a change in Sea Surface Temperature?

What happens when a hurricane Makes Landfall? How long does it take for the change to happen?

The model is described by Emanuel, K.A., 1995: The behavior of a simple hurricane model using a convective scheme based on subcloud-layer entropy equilibrium. J. Atmos. Sci., 52, 3959-3968.