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Piha-The Ditch ratings
Quality on a good day: 3.0
Consistency of Surf: 3.0
Difficulty Level: 3.0
Crowds: 3.0

Overall: 3.2

See all 18 ratings

Based on 3 votes. Vote


Surf Report Feed

Piha-The Ditch Swell Statistics, February: All Swell – Any Wind

The graph shows the variation of swells directed at Piha-The Ditch over a normal February, based on 2664 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 best grid node based on what we know about Piha-The Ditch, and at Piha-The Ditch the best grid node is 6 km away (4 miles).

The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These happened only 2% of the time. Green and yellow show increasing swell sizes and red represents biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell happens.

The diagram suggests that the most common swell direction, shown by the longest spokes, was WSW, whereas the the prevailing wind blows from the S. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Piha-The Ditch and out to sea. We group these with the no surf category of the bar chart. To keep it simple we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Piha-The Ditch, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical February, swells large enough to cause surfable waves at Piha-The Ditch run for about 98% 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.