Conditions at Katahama in May
May: Summer Swell, Summer Onshores
May marks the shift to the summer pattern, both in the ocean and the atmosphere. Swell from the optimal quadrant is actually abundant - SE (19.9%), ESE (16.7%), SSE (16.5%), and E (7.0%) make up over 60% of the observed waves, with the average period holding at 7.7s. The problem is the wind. Offshore flow from the west and northwest collapses to just 18.4% of the time, while onshore winds from WSW (13.8%), ENE (12.5%), E (11.0%), and SW (9.5%) dominate. Katahama's ESE-facing beach is now exposed to choppy, wind-blown conditions for the majority of the month. Average swell height drops slightly to 1.1m (3.5ft), so when the onshore wind is howling, the surf turns into messy, small, wind-slop. There are still occasional windows of clean surf in early morning during offshore breezes, but May is generally a month to pay close attention to the wind forecast. Water temps warm to 19.0°C, air to 19.1°C, and precipitation rises to 6.32 mm/day.
Average Spot conditions at Katahama in May
Swell history for May
Wind history for May
Swell quality
Analyze the groundswell consistency at Katahama 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 Katahama for your next trip in May.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Katahama 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 Katahama.