10-day surf forecast with Strike Scores for Shirahama Beach (Izu), Shimoda, Japan
Shirahama is the Izu Peninsula's premier surf beach, a consistent beachbreak that hosts competitions and draws surfers from across the Kanto region. The white sand beach is picture-perfect, and the wave works across a range of conditions, though it needs typhoon swells to really come alive. The scenic Izu Peninsula drive makes the journey worthwhile, and the area offers hot springs (onsen) to warm up after cold-water sessions.
Best day in the forecast: 2026-08-13 with a score of 51/100 (Fair)
Poor conditions overall: Average score 24/100. Look for spots with better forecasts.
Moderate alignment: Swell from 130° is 10° off optimal 140°, workable but not ideal.
Too big: 2.4m exceeds maximum 2.0m. Risk of closeouts.
Good period: 16s is 145% of ideal 11s. Clean, powerful groundswell.
Onshore/cross-shore: 33 km/h from 48° (NE). Destroying wave quality. Offshore range: 280°-360°.
-17 points: Previous days of onshore wind left residual chop ("morning sickness"), reducing wave quality.
Groundswell-dominant conditions (clean, long-period waves).
Poor conditions at Shirahama Beach (Izu). Either swell direction (130°), size (2.4m), or wind (33 km/h from 48°) is unfavorable. Consider other spots or wait for better conditions.
2.4m (7.9ft) swell from 130° (SE) at 16s period
Local wind-generated waves (choppy, short-period)
Moderate alignment: Swell from 164° is 24° off optimal 140°, workable but not ideal.
Too big: 3.0m exceeds maximum 2.0m. Risk of closeouts.
Good period: 15s is 136% of ideal 11s. Clean, powerful groundswell.
Onshore/cross-shore: 21 km/h from 55° (NE). Destroying wave quality. Offshore range: 280°-360°.
-21 points: Previous days of onshore wind left residual chop ("morning sickness"), reducing wave quality.
Poor conditions at Shirahama Beach (Izu). Either swell direction (164°), size (3.0m), or wind (21 km/h from 55°) is unfavorable. Consider other spots or wait for better conditions.
3.0m (9.8ft) swell from 164° (SSE) at 15s period
Poor alignment: Swell from 189° is 49° off optimal 140°, barely within workable range 125°-180°.
Too big: 3.3m exceeds maximum 2.0m. Risk of closeouts.
Onshore/cross-shore: 15 km/h from 84° (E). Destroying wave quality. Offshore range: 280°-360°.
Poor conditions at Shirahama Beach (Izu). Either swell direction (189°), size (3.3m), or wind (15 km/h from 84°) is unfavorable. Consider other spots or wait for better conditions.
3.3m (10.8ft) swell from 189° (S) at 15s period
No alignment: Swell from 209° is outside workable range 125°-180°. Wrong swell direction for this spot.
Too big: 2.8m exceeds maximum 2.0m. Risk of closeouts.
Onshore/cross-shore: 9 km/h from 140° (SE). Destroying wave quality. Offshore range: 280°-360°.
-11 points: Previous days of onshore wind left residual chop ("morning sickness"), reducing wave quality.
Poor conditions at Shirahama Beach (Izu). Either swell direction (209°), size (2.8m), or wind (9 km/h from 140°) is unfavorable. Consider other spots or wait for better conditions.
2.8m (9.2ft) swell from 209° (SSW) at 15s period
No alignment: Swell from 220° is outside workable range 125°-180°. Wrong swell direction for this spot.
Too big: 3.6m exceeds maximum 2.0m. Risk of closeouts.
Onshore/cross-shore: 9 km/h from 129° (SE). Destroying wave quality. Offshore range: 280°-360°.
Poor conditions at Shirahama Beach (Izu). Either swell direction (220°), size (3.6m), or wind (9 km/h from 129°) is unfavorable. Consider other spots or wait for better conditions.
3.6m (11.8ft) swell from 220° (SW) at 16s period
No alignment: Swell from 224° is outside workable range 125°-180°. Wrong swell direction for this spot.
Onshore/cross-shore: 8 km/h from 218° (SW). Destroying wave quality. Offshore range: 280°-360°.
Poor conditions at Shirahama Beach (Izu). Either swell direction (224°), size (3.3m), or wind (8 km/h from 218°) is unfavorable. Consider other spots or wait for better conditions.
3.3m (10.8ft) swell from 224° (SW) at 16s period
Too big: 2.5m exceeds maximum 2.0m. Risk of closeouts.
Onshore/cross-shore: 20 km/h from 61° (ENE). Destroying wave quality. Offshore range: 280°-360°.
Poor conditions at Shirahama Beach (Izu). Either swell direction (224°), size (2.5m), or wind (20 km/h from 61°) is unfavorable. Consider other spots or wait for better conditions.
2.5m (8.2ft) swell from 224° (SW) at 15s period
Poor alignment: Swell from 98° is 42° off optimal 140°, barely within workable range 125°-180°.
Marginal size: 1.9m is 0.6m from ideal 1.3m.
Perfect period: 12s is at or above ideal 11s. Long-period groundswell with maximum power.
Onshore/cross-shore: 19 km/h from 52° (NE). Destroying wave quality. Offshore range: 280°-360°.
Poor conditions at Shirahama Beach (Izu). Either swell direction (98°), size (1.9m), or wind (19 km/h from 52°) is unfavorable. Consider other spots or wait for better conditions.
1.9m (6.2ft) swell from 98° (E) at 12s period
Very low confidence (8-10 day forecast, conditions may change)
No alignment: Swell from 216° is outside workable range 125°-180°. Wrong swell direction for this spot.
Good size: 1.7m is within 15% of ideal 1.3m.
Perfect period: 11s is at or above ideal 11s. Long-period groundswell with maximum power.
Onshore/cross-shore: 6 km/h from 79° (E). Destroying wave quality. Offshore range: 280°-360°.
Surfable but not special at Shirahama Beach (Izu). The 1.7m swell from 216° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
1.7m (5.6ft) swell from 216° (SW) at 11s period
No alignment: Swell from 208° is outside workable range 125°-180°. Wrong swell direction for this spot.
Marginal size: 1.4m is 0.1m from ideal 1.3m.
Onshore/cross-shore: 6 km/h from 147° (SSE). Destroying wave quality. Offshore range: 280°-360°.
Surfable but not special at Shirahama Beach (Izu). The 1.4m swell from 208° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
1.4m (4.6ft) swell from 208° (SSW) at 11s period
Open-Meteo Weather API (wind/weather data)