Updated August 27, 2026 · Southeast Coast Editorial Team
A NOAA/NDBC buoy is one of the most useful objective references a coastal surfer can read, but the abbreviations can make a station page look more technical than it really is. The key is to separate total sea state from the pieces that create it.Start with WVHT: significant wave height
WVHT is significant wave height. NOAA describes significant wave height as roughly the average height of the highest one-third of waves in the measured sea state. It is an offshore instrument measurement, not a promise that every breaking wave at the beach will be that height. Shoaling, bathymetry, swell direction, local sandbars and wind all affect what finally breaks.
DPD: dominant wave period
Dominant period is the period associated with the most energetic part of the measured wave spectrum. Short periods often indicate nearby wind-driven energy. Longer periods can indicate energy that has traveled farther and is more organized. Period should always be read together with height and direction.
APD: average period
Average period summarizes the broader sea state. It can be much shorter than the dominant or swell period when a long-period swell is mixed with substantial short-period wind chop. That difference is useful: a 12-second swell can be present even while the total sea surface feels dominated by 4-second wind waves.
MWD: mean wave direction
Mean wave direction helps explain whether a coastline is exposed to the measured energy. A beach facing east is not equally exposed to every northeast, east, southeast or south swell. Headlands, capes, islands and nearshore bathymetry further change that exposure.
Wave summary: swell versus wind wave
Some NDBC stations provide a wave summary that separates swell height and period from wind-wave height and period. That is especially valuable for Southeast Coast surf because small long-period swell can exist under a larger field of local chop. The total wave height alone can hide that distinction.
Why station distance matters
An offshore buoy can be an excellent regional indicator while still being dozens of miles from your beach. The SEC Wave Report displays the selected buoy and approximate distance so you know whether the number is nearshore evidence or a broader regional reference. If a station is distant or stale, the report should say so instead of pretending the measurement is local.
Use buoy data as evidence, not a verdict
The best workflow is to combine buoy observations with a forecast, tide, local wind, beach orientation and—when available—a live camera or first-hand observation. That combination is why Southeast Coast separates observed data, forecast data and SEC analysis.