
Sumiyoshi March Surf HistoryBased on the last ten years data for this location this page gives daily averages and general conditions for the month of March. Of course these are just averages  it's worth reading carefully to understand exactly what they mean and to recognise the kind of variation you could expect on a trip.
Daily Average and Maximum/Minimum Swell Height (ft)
Day of the Month
These graphs show the maximum, minimum and average swell recorded on each day of the month over the last ten years. So the red part of the graph is the largest swell recorded on that day over ten years, the blue the smallest and the green bit is the average of all data on that day. This gives some idea of the range of possible swells and the variation over the month.
Daily Average and Maximum/Minimum Swell Period (Seconds)Day of the Month
Understanding this DataThese swell averages are calculated ONLY on swells of more than eight seconds period. This means this is the average height of a swell that's likely to produce ridable surf NOT an average of every wave heading toward the beach in a month.We show the day by day breakdown out of interest, not because you could statistically expect the '12th' to be regularly bigger than the '19th' in any given month. Even over a ten year period one huge swell will distort this slightly. What it does do is give an idea of the kind of variation that could be expected over the month. 