Misinterpreting hurricane forecasts

This is not the same cone map, the shaded area represents "50 percent or higher chance of experiencing wind speeds of at least 39 miles per hour" - ie. a simplified version of the map you recommend.

NHC tropical cyclone forecast tracks can be in error. This forecast uncertainty is conveyed by the track forecast "cone", the solid white and stippled white areas in the graphic. The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5. Historical data indicate that the entire 5-day path of the center of the tropical cyclone will remain within the cone about 60-70% of the time. To form the cone, a set of imaginary circles are placed along the forecast track at the 12, 24, 36, 48, 72, 96, and 120 h positions, where the size of each circle is set so that it encloses 67% of the previous five years official forecast errors. The cone is then formed by smoothly connecting the area swept out by the set of circles.

It is also important to realize that a tropical cyclone is not a point. Their effects can span many hundreds of miles from the center. The area experiencing hurricane force (one-minute average wind speeds of at least 74 mph) and tropical storm force (one-minute average wind speeds of 39-73 mph) winds can extend well beyond the white areas shown enclosing the most likely track area of the center. The distribution of hurricane and tropical storm force winds in this tropical cyclone can be seen in the Wind History graphic linked above.

Considering the combined forecast uncertainties in track, intensity, and size, the chances that any particular location will experience winds of 34 kt (tropical storm force), 50 kt, or 64 kt (hurricane force) from this tropical cyclone are presented in tabular form for selected locations and forecast positions. This information is also presented in graphical form for the 34 kt, 50 kt, and 64 kt thresholds.

To explain it better, consider a line chart versus a bar chart. Quantitatively, they display exactly the same data, to the same precision and the same fidelity and visual distortion. However, the two charts do not share the same interpretation. A bar chart places the visual emphasis on the magnitude of each individual data point, and is meant to let you easily compare the value of a data point to any other data point. Meanwhile, a line chart places the visual emphasis on the relative values of successive data point, and is meant to let you estimate rates of change and analyze both where data points not-yet-measured might end up and if rate of change is accelerating or decelerating.

The data that these charts are trying to convey is fundamentally a collection of lines--the possible paths that the eye of the hurricane may take. However, the means of its conveyance is by use of enclosed polygons on the map. These enclosed polygons convey a visual emphasis that all of the contained points share a feature in common. When discussing hurricanes, and given the context of the map, it is very easy to misinterpret that feature to be "this point will see damaging hurricane effects" instead of "this point is between the extremities of the most likely paths of the eye of the hurricane." Note too, how the labels I give are cumbersome: terse descriptions may again mean a label meant to evoke the latter turns out to evoke the former. A more visually accurate representation of the data would be to represent the cone of uncertainty with a collection of lines indicating the mean path and the edges. Perhaps you could add more tracks for more intermediate points to illustrate if the uncertainty is a smooth distribution or if there are weirder clusters (kind of like a spatial violin plot). You could also use varying lightness on the lines to indicate which are the center and which are the edges.

"The cone contains the probably path of the storm center but does not show the size of the storm. Hazardous conditions can occur outside of the code."

But I agree, the wind speed probability plot is much more useful. Like https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/204603.s...