[nws-changes] 20120914: ESTOFS Fwd: ADMIN NOTICE NOUS41 KWBC

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: [nws-changes] 20120914: ESTOFS Fwd: ADMIN NOTICE NOUS41 KWBC
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: Fri, 14 Sep 2012 09:29:44 -0600

-------- Original Message --------

254
NOUS41 KWBC 141316
PNSWSH

Technical Implementation Notice 12-43
NOAAs National Ocean Service Headquarters Washington DC
Relayed by National Weather Service Washington DC
915 AM EDT Fri Sep 14 2012

To:       Subscribers:
          -Family of Services
          -NOAA Weather Wire Service
          -Emergency Managers Weather Information Network
          -NOAAPORT
          Other NWS and NOS partners and employees

From:     Frank Aikman
          Chief, Marine Modeling and Analysis Programs
          NOS Office of Coast Survey

Subject:  Implementation of New Extratropical Surge and
Tide Operational Forecast System (ESTOFS) for the
Atlantic and Gulf coasts, Effective September 18, 2012

Universal Time (UTC), 800 AM EDT, the Extratropical Surge and
Tide Operational Forecast System for the Atlantic (ESTOFS
Atlantic) will be implemented on NOAAs Central Computer System
(CCS) operated by NCEP Central Operations (NCO). ESTOFS Atlantic
will provide users with nowcasts (analyses of near present
conditions) and forecast guidance of water level conditions for
the Atlantic and Gulf coasts. The forecast outputs will 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 ESTOFS is the ADvanced
CIRCulation (ADCIRC) finite element model. ADCIRC was developed
to perform high resolution simulations of time-dependent, free
surface circulation and transport problems in two and three
dimensions. ESTOFS uses the Two-Dimensional Depth Integrated
(2DDI) version of ADCIRC, which computes the water surface
elevation and barotropic depth-averaged currents. ADCIRC uses the
finite element method in space, taking advantage of highly
flexible, irregularly spaced grids.

nodes and 492,179 triangular elements. Coastal resolution
generally averages about 3 km. The open-ocean boundary is located
at the 60o 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. The performance of this grid
for astronomical tides was verified using tidal elevation data
from observation stations located throughout the domain.

ESTOFS is designed to provide water surface elevations caused by
storm surge and astronomical tide to the NCEP WAVEWATCH III (WW3)
wave model for coupling wave and water level predictions.
Therefore, ESTOFS set-up is designed to mimic WW3: it uses the
same Global Forecast System (GFS) atmospheric forcing (ESTOFS
applies 10 m wind speeds and sea level pressure from GFS), has
the same forecast cycle (4 times per day concurrent with GFS),
length (6 hour nowcast followed by a 180 hour forecast), and both
will run concurrently on the CCS.

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 station locations. GRIB2 files are created for each
hourly prediction during a forecast cycle, consisting of 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 nowcast/forecast
cycle, and consist of the hourly combined water level over the
native ESTOFS grid, or six-minute combined water level records at
station locations.

Beginning September 18 at 1200Z UTC, operational forecast
guidance from ESTOFS Atlantic will be available in the netCDF and
GRIB2 files described above via the NCEP server at NOAAs Web
Operations Centers (WOC) in the directory

Operational ESTOFS GRIB2 output will also be disseminated via
NCEPs NOAA Operational Model Archive and Distribution System
(NOMADS) server at

http://nomads.ncep.noaa.gov/

ESTOFS is monitored 24 x 7 by NCO. ESTOFS output is not currently
available via SBN or within AWIPS at this time.

For questions concerning these changes, please contact:

Dr. Jesse Feyen
Marine Modeling and Analysis Programs
Coast Survey Development Laboratory
NOAA/NOS/Office of Coast Survey
Silver Spring, MD
Jesse.Feyen@xxxxxxxx

For questions regarding the dataflow aspects with respect to the
NCEP server at the WOC, please contact:

Rebecca Cosgrove
NCEP/NCO Dataflow Team
College Park, MD
ncep.list.pmb-dataflow@xxxxxxxx

National Technical Implementation Notices are online at:

$$