Cook Inlet Operational Forecast System (CIOFS): Upper Bay

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]HHH.nc
  • 3-D field output: OFS.tCCz.YYYYMMDD.fields.[n|f]NNN.nc
  • 3-D field output on a regular grid: OFS.tCCz.YYYYMMDD.regulargrid.[n|f]NNN.nc
  • 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)

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.

A new three-dimensional Cook Inlet Operational Forecast System (CIOFS) was developed to better serve maritime user community. CIOFS was developed in a joint project of the NOAA/National Ocean Service/Office of Coast Survey, the NOAA/National Ocean Service/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). CIOFS provides users with nowcasts (analyses of near present) and forecast guidance of water levels, currents and water temperature out to 48 hours, four times per day. Aerial animations of the Cook Inlet as well as time series at particular stations or points of interests are available for the five parameters (water levels currents, temperature, and/or salinity). CIOFS will assist U.S. port authorities and mariners in efficiently navigating the Cook Inlet without compromising safety.

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

For more detailed information about CIOFS, please click here.

For more information about ROMS, please click here.

Disclaimer:
The Cook Inlet Operational Forecast System (CIOFS) 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, and water temperatures in CIOFS model domain. CIOFS 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.