JACKSONVILLE, Fla. – Starting this hurricane season, the National Hurricane Center will implement a new version of the forecast cone. This new cone will include a depiction of land-based tropical storm and hurricane alerts. This includes the United States, Hawaii, Puerto Rico and the U.S Virgin Islands.
This new cone replaces the version that only depicted coastal tropical storm and hurricane alerts. Adding inland alerts to the cone will help to further communicate wind risk during tropical events.
Notice how more alerts are shown with Hurricane Milton’s forecasted track, especially away from the coast. Along with inland alerts, there’s also an addition to the legend. Areas with multiple alerts in effect, more specifically areas that are under a Hurricane Watch and a Tropical Storm Warning, will show up as a dashed area to simplify the amount of layers on the map.
Hurricane Lane from 2018 is shown above with the new cone. The Hurricane Watch was included in this cone. This will help to emphasize that hurricane-force winds are likely even if the center of the storm is well to the west of Hawaii.
Another change is regarding the seven-day tropical weather outlook. In previous years, the outlook has shown systems with a low chance (less than 30%) of development as a yellow X. This included systems that had a near 0% chance of development in both the two-day and seven-day outlook.
Beginning this season, systems that are not expected to develop (near 0%) will be shown as a gray X, which you can see above. This also includes systems where development chances have fallen to near 0% and/or are being highlighted to communicate a significant rainfall/flooding threat.
One thing to note is that if a system has a near 0% chance of development in two days, but a greater chance in seven days, it will be displayed as a yellow X.
Hurricane season begins on May 1. Above is the list of names for this season. We will be sure to keep you updated as storms develop.