uk es it fr pt nl
Surf Break Rating

Rate Gull Rock


Surf Report Feed

Gull Rock Swell Statistics, March: All Swell – Any Wind

The figure illustrates the variation of swells directed at Gull Rock over a normal March, based on 2964 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the optimum grid node based on what we know about Gull Rock. In the case of Gull Rock, the best grid node is 51 km away (32 miles).

The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened only 73% of the time. Green and yellow illustrate increasing swell sizes and red illustrates the largest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell was forecast.

The diagram implies that the prevailing swell direction, shown by the biggest spokes, was WSW, whereas the the most common wind blows from the SSE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Gull Rock and away from the coast. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Gull Rock, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical March, swells large enough to cause surfable waves at Gull Rock run for about 13% of the time.

IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.