The National Hurricane Center is the authority on identifying and tracking named storms and hurricanes, and the seedling low-pressure centers that they form from. Local news outlets and national networks all use the NHC’s graphics and projections in their coverage, particularly when a storm nears land.
The center, based in Miami, makes all of its advisories, graphics and projections available on its website (www.nhc.noaa.gov, or simply www.hurricanes.gov). Here’s a guide to what is on there and where to find it.
The NHC provides tracking and analysis for storms in the Atlantic Ocean, as well as the Eastern Pacific (coast of Central America and Mexico and points west) and the Central Pacific (areas surrounding Hawaii).
Daily, even when there are no formed storms, the NHC puts out a Tropical Weather Discussion, an overview of any stormy areas and the general weather conditions in the ocean basins, four times a day (2 and 8 a.m. and p.m.). It also issues a Tropical Weather Outlook at those same times, detailing systems of concern and their formation chances – if there are none, the NHC issues a pleasant note of “Tropical cyclone formation is not expected.”
Prior to this year, that outlook extended out to 120 hours, or five days. This year, the NHC has extended that outlook out to seven days.
“Our reliability of that seven-day forecast is just as good as our five-day forecast has been,” said forecaster Robbie Berg, noting that models, and forecaster confidence in them, have improved in the past decade.
On the NHC graphical page, it uses a “code of crayons” — yellow for a low (last than 40 percent) chance of imminent development, orange for medium (40-60) chance and red for high (over 60 percent). It also graphs a “bubble” of where the potential development could be, and that area may show up larger in the path, with two extra days of potential area for development.
This will not change the famous “cone of the path of projected movement.” That will still give a five-day forecast track, although the NHC has said it has tested a seven-day forecast for its in-house products. Currently, the average error for five-day forecast points of storms is about 200 miles.
