Conditions at Oniguchi in January
January: Winter Consistency, Northwest Bias
January is the heart of the winter surf season at Oniguchi. The average swell height sits at 1.3m (around 4ft), with a 7.0s period-short-period, punchy and rideable, but not a long-period groundswell machine. The swell rose is heavily skewed toward the north: NW contributes 39.5%, NNW 13.7% and WNW 12.9%, while the ideal SSW/SW/WSW/W sector only adds up to about 7%. That means a substantial amount of January wave energy is angled away from the southwest-facing beach. What saves the month is wind: ideal offshore flow is present 54% of the time, with NNW winds dominating at 42.8% and NW adding another 18.4%. When a passing low-pressure system swings the swell direction into the WNW/W or southwest quadrant, expect clean, lined-up waves in the 3-5ft (0.9-1.5m) range. Air temperatures average 12.3°C, water temperature is 19.3°C, and precipitation is moderate at 3.29 mm/day.
Average Spot conditions at Oniguchi in January
Swell history for January
Wind history for January
Swell quality
Analyze the groundswell consistency at Oniguchi during January. 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 Oniguchi for your next trip in January.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Oniguchi for January. 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 Oniguchi.