Perspective

Tracking the paths of hurricanes

Interview | Jonathan Vigh, NCAR

22 August 2011  •  To find out where computer models project the path of a tropical cyclone, or how strong it may be, many hurricane followers call on the Web-based products developed by Jonathan Vigh, a postdoctoral researcher in NCAR’s Advanced Study Program. Vigh created the first generation of his real-time display tools while earning his doctorate at Colorado State University. This August, he unveiled an NCAR-based version called the Tropical Cyclone Guidance Project. Every six hours the site generates easy-to-parse graphics that portray the projections of future storm intensity and track for many of the forecast aids used by the National Hurricane Center (NHC). These span the range of complexity from full-physics dynamical models to simple statistical algorithms based on persistence and climatology.

Jonathan Vigh

Why do people go to your site?

I suspect that most people like the site’s simple, clear visualizations of the forecast aids. People have a keen interest in seeing the same information that hurricane specialists are using as they prepare the official forecasts. Another purpose of the site is to disseminate structure-based information, such as the vortex data messages (VDMs) taken by reconnaissance aircraft flying through a storm. Right now the site provides all VDMs for a given storm in one text file. In the near future, I plan to include plots of structure parameters over the storm’s life history, such as the radius of maximum winds. These plots will help forecasters and researchers visualize how these parameters have changed over the life of the storm.

Finally, and this might be most important, the site is meant to serve as a prototype for an open, real-time repository of forecast aids. Several organizations already collect and maintain their own repositories, but they often place restrictions on these data and do not always share these with the wider community in real time. This project is intended to fill that gap and encourage the development of new forecast aids.

Who are the most frequent visitors?

The user base is very diverse. The site is popular with National Weather Service forecasters from coastal regions; local and national emergency managers seeking to understand the reasoning behind NHC’s official forecasts; government agencies like NASA tasked with protecting equipment and resources; corporate users such as FedEx, who can experience large disruptions from hurricanes; and energy traders, who avidly monitor changes in the models.

I’ve been told that field programs use the site in their planning briefings, and local TV meteorologists sometimes use the plots on the air to explain why the official forecast track may have changed. I’ve also gotten e-mails from NHC hurricane specialists who told me they use the site when they’re off duty to keep up with the latest model developments.

What do people like most about the site?

Although it’s relatively easy to plot these data, it’s pretty difficult to make the presentation consistent. While Web 2.0 has become the rage for many applications, I think many people prefer to just click on a plot and get it right away without having to go through a bunch of interactive features. Also, not all smartphones can run the more sophisticated Web presentation technologies. I think a simple PNG image is really the easiest, most straightforward way to make this information as accessible as possible.

How does this relate to your current research at NCAR?

Over the last few years, my work has focused on the intensity and structural changes that occur during the formation of a hurricane eye. Based on my results, I’ve come to think that structure parameters are really important to a storm’s evolution. I hope that putting real-time observations on this site will spur a greater awareness of the importance of structure. In the next few months, I plan to begin disseminating the aircraft-based structure information in a format that can be used to develop new forecast aids for structure and intensity.