Posted on June 3, 2026
Maneuvering a 1,000 foot long container ship through a waterway isn’t guesswork. Vessel pilots rely on real-time data to understand changing ocean and weather conditions in order to safely bring a ship into port. For 35 years, NOAA’s Physical Oceanographic Real-Time System (PORTS®) has delivered this critical information to seaports nationwide, helping to keep mariners safe and maritime commerce moving.
PORTS was established in 1991, with the first system in Tampa Bay, Florida. Today, the program boasts 41 systems serving more than half of the nation’s top 175 U.S. seaports. Over 90% of U.S. cargo imports and exports and more than $1.3 trillion by value transit through the seaports served by NOAA PORTS annually, and PORTS plays an important role in ensuring this happens safely and efficiently. Since its establishment, economists estimate that NOAA PORTS has contributed to a 33% reduction in maritime accidents and a 59% reduction in vessel groundings.
But how does it work?
Establishing a PORTS
NOAA PORTS is a public-private partnership program. CO-OPS establishes each PORTS in collaboration with local users and customizes the system to meet their needs. Over 10 different types of data are available through PORTS, from water levels, currents, and salinity, to atmospheric pressure, wind, water temperature, visibility, waves, and bridge air gap (the available space under a bridge for a ship passage).
The largest PORTS installation consists of over 100 individual sensors, while some of the smallest consist of a single water level sensor and colocated meteorological sensors. It all depends on what local partners need.
PORTS Spotlight
In February 2026, CO-OPS established Boston Harbor PORTS, bringing a new level of situational awareness to one of the nation’s busiest seaports. The Port of Boston is a major maritime hub for the region, supporting 66,000 jobs and delivering billions of dollars in annual revenue. The system features a current meter and meteorological station and integrates data from NOAA’s Boston Harbor National Water Level Observation Network station.
Data Delivery
Once the sensors are installed, they undergo rigorous quality control to ensure their data are accurate and reliable. CO-OPS specialists monitor the data 24/7 to ensure these standards are met. PORTS data are then displayed publicly on NOAA’s Tides and Currents website, providing commercial and recreational mariners alike the information they need to navigate with confidence.
Navigating with PORTS
Mariners rely on PORTS information every day, multiple times a day, to plan transit schedules, set shipping priorities, and navigate safely in changing conditions. Each seaport and their data needs are different, but the flexibility and quality of PORTS plays an important role in helping them operate smoothly.
Keep reading to see some examples of how mariners use PORTS in their work.
- Chesapeake Bay North PORTS: Navigating a ship under a bridge requires careful measurements. Large container ships on their way to the Port of Baltimore have to pass under the Chesapeake Bay Bridge, a twin span bridge that sees lots of vehicle traffic. The Chesapeake Bay PORTS features two air gap systems on the bridge, providing vessel operators with real-time information on the available space under both spans of the bridge so they can pass under safely. And these are just two of the 70 sensors in the Chesapeake Bay North PORTS!
- Jacksonville PORTS: On the St. John’s River near the Port of Jacksonville, cross-channel currents can be a problem for deep-draft vessels transiting in the area. NOAA’s Jacksonville PORTS features several current meters along the St. John’s approach channel and in the river, providing St. John’s Bar Pilots with real-time data on tidal current speed and direction. The pilots use this information daily to inform anchorage procedures and adhere to speed restrictions that help protect marine mammals.
- Mobile Bay PORTS: In Mobile Bay, dense fog is common in the late winter and early spring, creating a navigational hazard that can lead to significant delays in vessel traffic to and from the Port of Mobile. Vessel operators rely on NOAA’s Marine Channels Forecast (MCF) system to stay safe even when the fog rolls in. The MCF provides visibility forecasts at 19 different points along the area’s shipping channel. Together with real-time observations from Mobile Bay PORTS, the MCF allows mariners to anticipate when they might encounter fog conditions.
- Los Angeles/Long Beach PORTS: Today’s giant container vessels have a huge sail area and strong winds can make it difficult to keep them safely on course. In Los Angeles and Long Beach Harbor, pilots rely on data from the Los Angeles/Long Beach PORTS to determine how many and what power tugs are required to safely move a particular ship. The pilots rely on this data every windy day to know when— or when not—- to move vessels, helping keep this busy seaport moving smoothly.
- PORTS in the Great Lakes: On the Great Lakes, water levels can change quickly due to shifts in prevailing winds. These water level changes can have significant impacts on large vessels: differences of a few feet of water can mean smooth sailing or running aground. There are three PORTS in the Great Lakes providing real-time water level data, along with currents and winds. These data help pilots plan vessel movements, even when conditions change rapidly.
Whether measuring the air gap for safe passage under a bridge or forecasting visibility conditions along a shipping channel, NOAA PORTS plays an important role in keeping maritime commerce moving. Mariners rely on PORTS every day to make timely, accurate, and informed navigational decisions. PORTS data are available for free online and are accessible by anyone, at any time, from anywhere.
