New York and New Jersey Operational Forecast System (NYOFS)

Notice of NOS OFS product changes

Effective on or about August 2024, the names of the model output files will officially be transitioned to the following format:

  • Stations: OFS.tCCz.YYYYMMDD.stations.[nowcast|forecast].nc
  • 2-D surface field output: OFS.tCCz.YYYYMMDD.2ds.[n|f]
  • 3-D field output: OFS.tCCz.YYYYMMDD.fields.[n|f]
  • 3-D field output on a regular grid: OFS.tCCz.YYYYMMDD.regulargrid.[n|f]
  • Where:
  • OFS refers to the name of the model (e.g. cbofs, sfbofs, leofs)
  • [nowcast/forecast] or [n/f] denotes either the nowcast or forecast results
  • YYYYMMDD refers to the date of the model run
  • CC refers to the cycle of the day (e.g. 06, 12)
  • HHH is the nowcast or forecast hour (e.g. 001, 002)

Starting April 1, 2024, model output files with both the existing and the new file formats will be made available here for users to update and test code used to automate the download of the model output. As August 2024 draws near, this notice will be updated with the exact date of the transition.

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

The Port of New York and New Jersey Operational Forecast System (NYOFS) provides mariners, port managers and spill response teams with nowcast (present conditions) and forecast (future conditions) hydrodynamic model-based water levels and currents. NYOFS products include time series, plots and animations of water levels and currents that are disseminated through this website. NYOFS nowcast and forecast products allow port managers and shippers to make sound decisions regarding maximum tonnage and passage times without compromising safety. Providing reliable information on water levels and currents is an important component of NOAA's mission to promote safe and efficient navigation in our nation's waterways.

The cornerstone of NYOFS is an advanced three-dimensional hydrodynamic model that uses realtime water-level and wind data and other inputs to predict the water levels and currents at thousands of locations throughout the harbor. Based upon feedback received from local mariners, specialized time-series graphics are produced at the important locations shown on the map above. This system is an important complement to NOAA's Physical Oceanographic Real-Time System (PORTS®) now operating in the harbor. PORTS® provides accurate real-time oceanographic and meteorologic data from seven stations to local users.

The Nowcast Forecast model system was developed in NOS's Coast Survey Development Laboratory (CSDL) and is maintained by NOS's Center for Operational Oceanographic Products and Services (CO-OPS). A key component of CO-OPS's operational monitoring is the continuous (24 hours a day, 7 days a week) quality assurance and control of NYOFS inputs, procedures and products.

The system runs in both nowcast and forecast modes. The nowcast mode is driven by real-time water levels and winds from the New York/New Jersey PORTS®, and is updated hourly. The forecast mode performs 30-hour forecasts four times a day. Primary inputs for this mode include information from the nowcast model, tidal harmonics, and forecasts of subtidal water levels and winds provided by NOAA's National Weather Service numerical models.

Historically, mariners in the United States had to depend solely on NOAA's Tide Tables for the best estimates of expected water levels and currents. These tables provide accurate predictions of the astronomic tides and currents due to the gravitational effects of the moon and sun combined with the rotation of the Earth. However, they cannot predict changes due to wind, atmospheric pressure and river flow, which are often significant. Furthermore, in most water bodies, predictions are available at a few locations only. New technology such as NYOFS and PORTS®, combined with the Tide Tables, provides the nation's mariners with the best available information. These models are also used by NOAA's Office of Response and Restoration to improve its response to spills of oil and hazardous materials.

The New York/New Jersey Operational Forecast System (NYOFS) 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 New York/New Jersey bays, and rivers. NYOFS 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.

During extreme weather conditions, water level forecast guidance data are released for public utility and should be used with appropriate caution.