10-day surf forecast with Strike Scores for Periscopes, East Sumbawa, Indonesia
Periscopes is a long, rippable right reef break in East Sumbawa that produces tight barrels over a safe reef platform. The wave works best at high tide and provides a quality alternative to Lakey Peak, offering longer rides with good barrel and turn sections. Its exposure to dry season SE trade winds can cause afternoon blow-out, making morning sessions essential for clean conditions.
Best day in the forecast: 2026-08-14 with a score of 78/100 (Good)
Fair recommendation: Periscopes has 8 Good days but no Firing days. Decent for a local session.
Moderate alignment: Swell from 217° is 12° off optimal 205°, workable but not ideal.
Marginal size: 1.4m is 0.3m from ideal 1.6m.
Perfect period: 14s is at or above ideal 14s. Long-period groundswell with maximum power.
Onshore/cross-shore: 7 km/h from 181° (S). Destroying wave quality. Offshore range: 330°-30°.
Groundswell-dominant conditions (clean, long-period waves).
Good surfable conditions at Periscopes. 1.4m swell from 217° with manageable wind. Solid session guaranteed.
1.4m (4.6ft) swell from 217° (SW) at 14s period
Moderate alignment: Swell from 218° is 13° off optimal 205°, workable but not ideal.
Marginal size: 2.3m is 0.6m from ideal 1.6m.
Good period: 17s is 121% of ideal 14s. Clean, powerful groundswell.
Onshore/cross-shore: 7 km/h from 188° (S). Destroying wave quality. Offshore range: 330°-30°.
Good surfable conditions at Periscopes. 2.3m swell from 218° with manageable wind. Solid session guaranteed.
2.3m (7.5ft) swell from 218° (SW) at 17s period
Moderate alignment: Swell from 216° is 11° off optimal 205°, workable but not ideal.
Too big: 2.5m exceeds maximum 2.4m. Risk of closeouts.
Perfect period: 16s is at or above ideal 14s. Long-period groundswell with maximum power.
Good surfable conditions at Periscopes. 2.5m swell from 216° with manageable wind. Solid session guaranteed.
2.5m (8.2ft) swell from 216° (SW) at 16s period
Too big: 2.8m exceeds maximum 2.4m. Risk of closeouts.
Onshore/cross-shore: 10 km/h from 215° (SW). Destroying wave quality. Offshore range: 330°-30°.
Surfable but not special at Periscopes. The 2.8m swell from 216° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
2.8m (9.2ft) swell from 216° (SW) at 16s period
Onshore/cross-shore: 9 km/h from 203° (SSW). Destroying wave quality. Offshore range: 330°-30°.
Moderate alignment: Swell from 215° is 10° off optimal 205°, workable but not ideal.
Marginal size: 2.2m is 0.6m from ideal 1.6m.
Perfect period: 15s is at or above ideal 14s. Long-period groundswell with maximum power.
Onshore/cross-shore: 11 km/h from 235° (SW). Destroying wave quality. Offshore range: 330°-30°.
Good surfable conditions at Periscopes. 2.2m swell from 215° with manageable wind. Solid session guaranteed.
2.2m (7.2ft) swell from 215° (SW) at 15s period
Good alignment: Swell from 209° is 4° off optimal 205°, still within prime range.
Too big: 3.1m exceeds maximum 2.4m. Risk of closeouts.
Onshore/cross-shore: 13 km/h from 188° (S). Destroying wave quality. Offshore range: 330°-30°.
Surfable but not special at Periscopes. The 3.1m swell from 209° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
3.1m (10.2ft) swell from 209° (SSW) at 17s period
Good alignment: Swell from 211° is 6° off optimal 205°, still within prime range.
Onshore/cross-shore: 9 km/h from 218° (SW). Destroying wave quality. Offshore range: 330°-30°.
Good surfable conditions at Periscopes. 2.2m swell from 211° with manageable wind. Solid session guaranteed.
2.2m (7.2ft) swell from 211° (SSW) at 16s period
Very low confidence (8-10 day forecast, conditions may change)
Perfect alignment: Swell from 205° is within 5° of optimal 205°.
Too big: 2.7m exceeds maximum 2.4m. Risk of closeouts.
Onshore/cross-shore: 10 km/h from 207° (SSW). Destroying wave quality. Offshore range: 330°-30°.
Good surfable conditions at Periscopes. 2.7m swell from 205° with manageable wind. Solid session guaranteed.
2.7m (8.9ft) swell from 205° (SSW) at 16s period
Good alignment: Swell from 210° is 5° off optimal 205°, still within prime range.
Good size: 2.1m is within 15% of ideal 1.6m.
Onshore/cross-shore: 7 km/h from 214° (SW). Destroying wave quality. Offshore range: 330°-30°.
Good surfable conditions at Periscopes. 2.1m swell from 210° with manageable wind. Solid session guaranteed.
2.1m (6.9ft) swell from 210° (SSW) at 16s period
Open-Meteo Weather API (wind/weather data)