Max Mayfield said that he wanted the following epitaph placed on his tombstone: “Don’t pay attention to the skinny black line.†The “skinny black line†that Max was referring to is the forecast track placed on t he Tropical Cyclone Track and Watches/Warning graphic by the National Hurricane Center. The graphic has come to be known as the Cone of Uncertainty.
It shows the office NHC forecast track, but also shows a white cone that signifies the 10 year forecast error and any watches or warnings that are in effect. Many people in the hurricane zone have come to rely heavily on this graphic for their own personal actions during a hurricane situation.
This month’s Bulletin of the American Meteorological Society presents a study on misinterpretations of the Cone of Uncertainty in Florida during the 2004 Hurricane Season. A prime example to study came during Hurricane Charley in August of that year. The rapid strengthening hurricane made landfall in Charlotte County in Southwest Florida on Friday, August 13th. The hurricane jogged to the right at the last minute, deviating slightly from the official forecast track, but remaining well within the uncertainty cone and the hurricane warning. Some people said they were surprised when the storm hit them directly, as they were expecting it to hit further north in the Tampa Bay area.
After the 2004 hurricane season, the NHC conducted an online survey to offer alternatives to the graphic used during the 2004 season. They presented the current graphic, a graphic which showed the forecast positions, but not the skinny black line and a third option that showed only the cone, no highlighted in white, with no positions or skinny black line. Out of 962 responses, the original graphic (option1) was preferred (540 respondents.) Graphic 2, with the cone and positions, but no skinny black line was favored by only 121 respondents. Graphic 3, with no track or positions, only a series of circles around an expected position was favored by 201 respondents. 33 had no preference and 67 could not decide. So the graphic has remained the same.
It is still subject to misinterpretation, but I feel that it is incumbent on us in the media to communicate threat information, risk and uncertainty as clearly as possible to the consumer, the general public. Your thoughts?
