G-Land (Grajagan) Swell Window

Java, Indonesia · part of the G-Land (Grajagan) spot guide

Swell window (from): 160°–250° (SSE–WSW)
Best direction: ~220° (SW)
Period sweet spot: 14–18 s
Open-ocean height (Hs): 5–15 ft
Resulting faces: 3–15 ft

Open-ocean vs. the face: the heights on buoys and forecast models are significant wave height (Hs) in deep water. What you ride is the breaking face, which depends on period, direction and this break's bathymetry — that's why the two rows above differ. PierMonkey's spot ratings already do this conversion for you.

It wants southwest to south-southwest, best around 200–240°, on long period — 14 to 18 seconds is ideal, with 12 seconds the threshold. Long period is what lets the swell wrap and refract cleanly down the reef and link the sections.

The reef amplifies the swell, so the breaking face runs larger than the open-ocean reading: a 1.5 m reading is a fun head-high day, and a solid 3 m at long period is well-overhead and barreling. The model height and the face are two different numbers.

The storm corridor

Typical swell corridor to G-Land (Grajagan): Roaring Forties lows sending long-period SW groundswell to Java’s SE tip — Typical swell corridor (schematic straight line): Roaring Forties lows sending long-period SW groundswell to Java’s SE tip.