Conditions at Kugenuma in May
May: Summer Monsoon Ramp-Up
May is where Kugenuma's low season begins in earnest. The average swell remains physically present - S dominates with 25.8%, SSE at 24.7% and SSW at 18.6% - but the wind climate turns largely adverse. SSW wind is now the second-largest wind category at 19.3%, with SW at 11.9% and S at 12.9%. Combined with the S/SSW swell, this supplies plenty of waves, but almost always with a textured, windblown face. The ideal-wind share drops to 16%, mostly tied to morning windows with N/NNE flow. Average wave height has dipped to 0.7m and the period stays at 7.8s, so most days are small and grovelly. Water temperature rises to 18.7°C, and air temperatures average 16.9°C with rainfall increasing to 4.45 mm/day. The meteorological driver is the developing summer monsoon: as the Pacific subtropical high strengthens, the pressure gradient across Japan becomes increasingly southerly. For Kugenuma, that means marginal, onshore-dominated surf unless a passing front or late-season low disrupts the pattern.
Average Spot conditions at Kugenuma in May
Swell history for May
Wind history for May
Swell quality
Analyze the groundswell consistency at Kugenuma during May. Based on historical data, there is a % probability of groundswell occurring this month. The chart below provides a detailed breakdown of the average wave height distribution, offering deep insights into the swell quality and surf potential you can expect at Kugenuma for your next trip in May.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Kugenuma for May. Our analysis shows that favorable offshore or side-shore winds coincide with surfable swell approximately % of the time. The accompanying graph illustrates the average size distribution of waves during these optimal wind windows at Kugenuma.