The Surge and Tide Operational Forecast System 2D Global (STOFS-2D-Global) provides users with nowcasts (analyses of near present conditions) and forecast guidance of water level conditions for the entire globe. The forecast outputs include water levels caused by the combined effects of storm surge and tides, by astronomical tides alone, and by sub-tidal water levels (isolated storm surge) out to 180 hours. The hydrodynamic model employed by STOFS-2D-Global is the ADvanced CIRCulation (ADCIRC) finite element model. The unstructured grid used by STOFS-2D-Global consists of 12,785,004 nodes and 24,875,336 triangular elements. Coastal resolution is up to 80 m for the U.S. West Coast and Alaska, up to 90-120 m for the Pacific Islands including Hawaii, Guam, American Samoa, Marianas, Wake Island, Marshall Islands, and Palau, and up to 120 m for the U.S. East Coast and Puerto Rico. The flood plain extends overland to approximately 10 m elevation above MSL for the U.S. East Coast, and up to 20 m elevation above MSL for the Pacific Islands. STOFS-2D-Global includes internal tides and sea-ice effect on wind drag. STOFS-2D-Global water level forecast guidance is referenced to Local Mean Sea Level (LMSL) for gridded and station output (SHEF files are referenced to MLLW).
STOFS-2D-Global output files are provided here in two formats: structured GRIB2 files for the contiguous U.S. East region (2.5 km resolution), contiguous U.S. West region (2.5 km resolution), Alaska (6 km resolution), Hawaii (2.5 km resolution), Guam (2.5 km resolution), North Pacific (10 km resolution), and Puerto Rico (1.25 km resolution) grids, and unstructured NetCDF files on the native STOFS-2D-Global finite element grid, consisting of ~13 million nodes. NetCDF output is also provided at 1,688 verification sites globally. GRIB2 files are created for hourly forecasts during each forecast cycle, consisting of hourly records of combined water level (surge with tide), harmonic tidal prediction (astronomical tides), and sub-tidal water levels (the isolated surge). There are also GRIB2 files that contain an entire run cycle, for each of combined, harmonic tidal prediction, and sub-tidal water levels. NetCDF files contain an entire run cycle, and consist of the hourly combined, harmonic tidal prediction, and sub-tidal water levels over the native STOFS-2D-Global grid, or six-minute combined, harmonic tidal prediction, and sub-tidal water level records at 1,688 verification sites. SHEF files are provided, containing half hourly water levels for the forecast period at the 385 verification sites.
STOFS web page: Storm Surge