Wave Observations : Hilo, Hawaiʻi Island
NOTE: Click on the plot below for data at a specific time.
NOTE: This instrument does not report in real-time. New data are retrieved periodically.
start date: : temperature: wave height:
Disclaimer: Near real-time data have not been quality controlled.
Disclaimer: Data are released in compliance with real-time quality control standards.
Disclaimer: Real-time data are provided as raw and unaltered. Results of quality control checks are provided within the data set.
Figure 1. The above figure shows the swell directional spectrum of the wave energy field, which is calculated from the wave buoy accelerometer data over a 26-minute time span. This depicts the direction from which waves are propagating as a function of wave period (duration between wave crests) and wave energy. Wave direction is labeled around the circumference of the plot in compass degrees (0° = North, 90° = East, 180° = South, 270° = West). Wave period is labeled in red in seconds, with longer periods near the center of the plot and shorter periods towards the outer edge. In order to characterize the swell, this plot limits itself to wave periods greater than 8 seconds (see the full directional spectrum below to view short-period wind waves). Warmer colors on the figure represent higher levels of wave energy (bigger waves) while cooler colors indicate less wave energy (smaller waves). In this way, one can quickly see how waves have varied in size, speed, and direction at the buoy location. The corresponding significant wave height (Hs), peak wave period (Tp), and peak wave direction (Dp) are also listed.
Figure 2. The above figure shows the full directional spectrum of the wave energy field. While Figure 1 limits itself to swells with a wave period greater than 8 seconds, this figure also includes shorter period wind waves. Swell waves are produced by distant storm systems far offshore, producing higher period (longer wave length) waves. Waves generated by local winds have a much lower period (shorter wave length) and can serve as an indicator of how choppy the water is.
Figure 3. The above figure shows the temporal spectrum of the wave energy field for the past 72 hours. This depicts how both wave period and wave energy have changed over time, with longer periods near the top of the plot and shorter periods towards the bottom. As in Figure 1, warmer colors represent higher levels of wave energy (bigger waves) while cooler colors indicate less energetic waves (smaller waves). Unlike Figure 1, this plot does not indicate wave direction.
This WaveWatch III (WW3) global wave model output shows forecasts of wave conditions associated with different wave events. The WW3 spectral bulletin used to generate this figure was retrieved from NOAA/NCEP/NWS. The top panel shows significant wave heights in feet, the middle panel illustrates the direction that peak waves are travelling from in degrees (0° = North, 90° = East, 180° = South, 270° = West, 360° = North), and the bottom panel plots peak wave periods in seconds. Each color indicates a different wave event from the forecasted wave spectrum, which typically arise due to differing storm or wind conditions. The solid black curve in the top panel is the total significant wave height model forecast (i.e., the sum of all wave events). The black dots towards the left-hand side of each panel are the most recent observations from the buoy itself (if any) for comparison with the model.
*Note that the closest available WW3 spectral bulletin is used for this figure. The model does not provide bulletins for all locations so there may be discrepancies between the wave buoy data and the model output due to differences in location.
The PacIOOS wave buoy off Hilo (CDIP #188; NDBC #51206) measures waves northeast of Hilo Harbor approximately 4 miles (6 km) offshore of Leleiwi Point on the windward (eastern) coast of Hawaiʻi Island (Big Island) in the State of Hawaiʻi. Data are transmitted every half hour. Moored in water 347 meters deep, this Datawell Directional Waverider buoy is equipped with three accelerometers measuring north/south, east/west, and vertical displacements, allowing it to measure both wave direction and wave energy. Such information promotes safe transit entering and exiting Hilo Harbor, offers real-time data to recreational ocean users, and provides critical information for coastal hazard and low-lying inundation forecasts.
The Hilo wave buoy is owned and managed by PacIOOS. The Joint Institute for Marine and Atmospheric Research (JIMAR) of the University of Hawaiʻi at Mānoa provided the initial funding to purchase this buoy. Data are managed by the Coastal Data Information Program (CDIP) at Scripps Institution of Oceanography of the University of California, San Diego (UCSD). Long-term partnerships between PacIOOS, the U.S. Army Corps of Engineers (USACE), and CDIP enable data streaming into the PacIOOS website and PacIOOS Voyager.
The PacIOOS wave buoy off Hilo, Hawaiʻi, also provides Sea Surface Temperature Observations in real-time.