Removal of Content Advisory - April 2024

Advisory to Geophysical Fluid Dynamics Laboratory (GFDL) Vortex Tracker for Tropical Cyclones users: As of the beginning of April 2024, all support assets for Geophysical Fluid Dynamics Laboratory (GFDL) Vortex Tracker for Tropical Cyclones will be removed from the DTC website. Users should download all reference materials of interest prior to April 2024.

GFDL Vortex Tracker

sea and sky image

Notice: as of October 2021, DTC has ceased all activities supporting the GFDL vortex tracker user community. For more details see the full announcement.


The GFDL vortex tracker system consists of the source code for the GFDL vortex tracker as well as the tracker utility.

The standalone Geophysical Fluid Dynamics Laboratory (GFDL) vortex tracker is a program that objectively analyzes forecast data to provide an estimate of the vortex center position (latitude and longitude), and track the storm for the duration of the forecast. Additionally, it reports metrics of the forecast storm, such as intensity (maximum 10-m winds and minimum mean sea level pressure (MSLP)), structure (wind radii for 34, 50 and 64 knot thresholds in each quadrant), radius of the outermost closed isobar (ROCI), and optionally integrated kinetic energy (IKE), storm surge damage potential (SDP) and cyclone thermodynamic phase at each output time.

The software can track either storms that exist at model initialization time or storms that develop during the forecast (cyclogenesis). The GFDL vortex tracker requires the forecast grids to be on a cylindrical equidistant, latitude-longitude (lat/lon) grid. Forecast files can be in GRIB (GRIB1 or GRIB2) or, starting with v3.9a, NetCDF format.