Near Shore Wave Prediction System (NWPS) Output

Atmospheric River in the Pacific Northwest and Northern Rockies this Weekend

A Pacific storm and atmospheric river will impact the Pacific Northwest states and northern Rockies this weekend, bringing locally heavy low elevations rain and heavy high elevation snow in the mountains. By Sunday over the Interior Northwest, rain combined with snowmelt will increase the risk of flood hazards. Flood Watches are in effect. Read More >

These models forecasts are produced by WFO Mount Holly, NJ, using the NWPS wave models and the Real Time Ocean Forecast System.

The NWPS output is used as guidance to produce WFO Mount Holly. It is only experimental and it may differ from the official forecast. For the official marine forecast graphics go to: WFO PHI Official Marine Forecast Graphics.

NWPS accounts for the following physics:

Wave propagation in time and space, shoaling, refraction due to current and depth, frequency shifting due to currents and non-stationary depth.

Wave generation by wind.

Three- and four-wave interactions.

Whitecapping, bottom friction and depth-induced breaking.

Dissipation.

Wave-induced set-up.

Propagation from laboratory up to global scales.

Transmission through and reflection (specular and diffuse) against obstacles.

Diffraction.

In here you will see 3-hourly forecast outputs for significant wave height, peak wave direction, peak wave period, and significant swell height (heights in feet and periods in seconds). Our local version of NWPS also uses input from WAVEWATCH III for boundary conditions.

NOTE: Significant Swell Height output from NWPS is the average height of the highest 1/3 of the group of waves with periods of 10 secs or longer.