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The Extratropical Surge and Tide Operational Forecast System for the
Atlantic (ESTOFS Atlantic) provides users with nowcasts (analyses of
near present conditions) and forecast guidance of water level
conditions for the Atlantic and Gulf coasts. The forecast outputs
includes 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 ESTOFS is the ADvanced CIRCulation
(ADCIRC) finite element model. The unstructured grid used by ESTOFS
Atlantic consists of 254,565 nodes and 492,179 triangular elements.
Coastal resolution generally averages about 3 km. The open-ocean
boundary is located at the 60 W meridian, where harmonic tidal
constituents from the global tidal model TPXO 6.2 are used to specify
tidal water surface fluctuations, while tidal potential forcing is
applied within the interior of the domain.
ESTOFS output files are provided in two formats: structured GRIB2
files for the contiguous U.S. (2.5 km resolution) and for Puerto Rico
(1.25 km resolution) grids, and unstructured NetCDF files on the
native ESTOFS finite element grid. NetCDF output is also provided at
observation station locations. GRIB2 files are created for hourly
predictions 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).
NetCDF files contain an entire run cycle, and consist of the hourly
combined water level over the native ESTOFS grid, or six-minute
combined water level records at observation station locations.
ESTOFS web page: