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Surf Report Feed

Imperial Pier (North and South) Swell Statistics, Winter: All Swell – Any Wind

This picture shows the variation of swells directed at Imperial Pier (North and South) through an average northern hemisphere winter, based on 8485 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the best grid node based on what we know about Imperial Pier (North and South). In the case of Imperial Pier (North and South), the best grid node is 35 km away (22 miles).

The rose diagram illustrates the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These were forecast only 0.8% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how often that size swell was forecast.

The diagram indicates that the dominant swell direction, shown by the biggest spokes, was WSW, whereas the the prevailing wind blows from the NW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Imperial Pier (North and South) and away from the coast. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are surfable at Imperial Pier (North and South), you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical northern hemisphere winter, swells large enough to cause good for surfing waves at Imperial Pier (North and South) run for about 99% 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.

FEATURE UPDATE: we now show red swell icons for 'open sea' swells that are travelling in an unfavourable direction for the surf break. In places, these swells may still wrap around coastlines and produce smaller waves at some breaks. They are also significant for windsurfers and other water users that tend to venture further off-shore.