Blenheim Beach Surf Stats

The figure describes the variation of swells directed at Blenheim Beach through an average April and is based upon 3360 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the most applicable grid node based on what we know about Blenheim Beach, and at Blenheim Beach the best grid node is 30 km away (19 miles). The rose diagram describes the distribution of swell directions and swell sizes, 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 were forecast only 48% of the time. Green and yellow represent increasing swell sizes and red shows the highest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the dominant swell direction, shown by the largest spokes, was ESE, whereas the the dominant wind blows from the SW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Blenheim Beach and out to sea. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Blenheim Beach, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause surfable waves at Blenheim Beach run for about 1.0% of the time.

read more