Inamuragasaki • Statistics for January

January: The Heart of the Winter Swell Window

January marks the core of Inamuragasaki's northern winter season, with the North Pacific low-pressure train firing up and sending consistent, mid-range energy toward the south-facing beach. The average swell checks in at just 0.7m (2.3ft) with an average period of 7.8s, meaning most days are small, punchy and rideable rather than powerful or hollow. Direction-wise, the southwest dominates: SW accounts for 29.2% of all swell, with SSW adding 10.3% and SSE/S another 10.0% combined - all prime directions for the beach. However, wave heights rarely push past 1.5m (4.9ft), so don't expect winter XXL here. The wind story is much more favourable: NNE winds blow 29.3% of the time and NE another 12.6%, while N and NNW contribute, giving the spot offshore or cross-offshore conditions about 58% of the time. With only 16% of hours classified as ideal, the rest of the time you'll be dodging moderately lumpy conditions, but when the Siberian high anchors cold, dry NW-NNE flow, the lines clean up beautifully. Air temperatures hover near 2.3°C (down to -7.0°C) and water temperature sits at 16.0°C, so a full winter wetsuit is non-negotiable.