Chesapeake Bay Operational Forecast System (CBOFS)

Notice of directory structure change on the NODD S3 bucket

The NODD AWS cloud is used to disseminate model outputs from National Ocean Service's operational forecast systems (OFS).

  • As of January 1, 2025, the new directory structure will be: /OFS/netcdf/YYYY/MM/DD, where
    • OFS refers to the name of the model (e.g. cbofs, ciofs, dbofs, gomofs, leofs, lmhofs, loofs, lsofs, ngofs2, sfbofs, sscofs, tbofs, wcofs)
    • YYYY refers to the year of the model run
    • MM refers to the month of the model run
    • DD refers to the day of the model run
  • The new directory structure will improve performance while accessing the model outputs.

Starting November 20, 2024, model output files will be available in the current and new directory structures. The current file directory structure is: OFS/netcdf/YYYYMM, where one single folder usually contains over 7000 files and a large amount of memory is required for the THREDDS applications.

The current directory and new structures will co-exist until January 1, 2025, when the current directory structure will be decommissioned.

(Please click on the map pins below to access the time series plots)

For decades, mariners in the United States have depended on NOAA's Tide Tables for the best estimate of expected water levels. These tables provide accurate predictions of the astronomical tide (i.e., the change in water level due to the gravitational effects of the moon and sun and the rotation of the Earth); however, they cannot predict water-level changes due to wind, atmospheric pressure, and river flow, which are often significant.

To better serve maritime user community, an upgraded three-dimensional version of the Chesapeake Bay Operational Forecast System (CBOFS) was developed by the NOAA/National Ocean Service/Office of Coast Survey in a joint project with the NOAA/NOS/Center for operational Oceanographic Products and Services (CO-OPS) and the NOAA/National Weather Service/National Centers for Environmental Prediction (NCEP) Central Operations (NCO) using Rutgers University's Regional Ocean Modeling System (ROMS). CBOFS generates water level, current, temperature and salinity nowcast and forecast guidance four times per day. Aerial animations of the whole Chesapeake Bay as well as time series at particular stations or points of interest are available for over 58 locations for the five parameters (water level, currents, temperature, and/or salinity).

CBOFS runs on NOAA's High Performance Computers (HPC) in a new Coastal Ocean Modeling Framework (COMF) developed by CO-OPS. As a result, CBOFS has direct access to National Weather Service operational meteorological products that it needs to run reliably.

The higher resolution and three-dimensionality of the new CBOFS along with the added current nowcast and forecast information and the additional reliability of running at NOAA's HPC will further assist U.S. port authorities and mariners in efficiently navigating the Chesapeake Bay without compromising safety.

For more detailed information about CBOFS, please click here.

For more information about ROMS, please click here.

Disclaimer: The Chesapeake Bay Operational Forecast System (CBOFS) has been implemented by NOAA's National Ocean Service (NOS) to provide the maritime user community with short-term predictions of water levels, water currents, water temperatures and salinity of the Chesapeake Bay. CBOFS uses a numerical hydrodynamic model to generate the nowcast and forecast information; therefore, they should be considered as model-generated nowcast and forecast guidance. For more detailed information related to the OFS disclaimer, please visit at the Disclaimers web page.