The high sea of 2026: part of the narrower beach is water.

The highest sea in the gauge record, and how past El Niños compare.

On 1–25 October 2026 the sea along this coast read +0.37 m above its 2017–2025 average, the highest month in the gauge record since 2014 (September read +0.29 m). October 2015 read +0.20 m and October 2023 +0.13 m; the 2015–16 El Niño peaked at +0.26 m. The +0.37 m is a gauge measurement. The comparison with the strong El Niño Octobers of 1982, 1997, 2015 and 2023 is an estimate, not a measurement at this beach: by it this October is about as high or higher, by a few centimeters. The 1982 and 1997 numbers come from the Acapulco gauge, transferred to this coast, and use a different baseline.

In past years October's high sea lasted into the winter: in 2014–2025 each October's level and the following November–January moved together (correlation 0.89, 12 years). That is an estimate from past Octobers, not a forecast for this winter.

Part of the narrower beach is high water.

In August and early September 2026 the beach at the wave (Z1 South point to Z5 Creek mouth) sat about 19 m narrower than its usual August–October position of 2016–2025 (range 14–25 m), read from three satellite images taken 1 August to 10 September. About 6 m (3–11 m) of that is explained by higher water in the current model; about 13 m (8–17 m) is not explained by water level alone, a shortfall that began in the 2025 rainy season.

The control beaches on either side lost only 5–6 m of sand. The sand at the wave swings more with El Niño than its neighbors do, and earlier dips since 2016 were as deep, so this is not yet a sign of lasting loss. These images are from before the October storms, which cut the beach back further in places.

How far up the sand a higher sea reaches.

At +0.37 m above normal, the waterline at the wave sits about 10 m farther up the sand than at normal sea level (8–13 m with that June–October slope taken 25% steeper or gentler), before tide and waves. The cove is steeper from November to May (about 1 in 22) than from June to October (about 1 in 27); each level uses the slope of its season. The August–September images above were taken when the sea stood lower than in October, which is why the water share there is smaller.

This is a simple geometric estimate: the waterline moves landward by sea level divided by beach slope. It is not a flood model. It leaves out tide, waves, storms and sand that moves, and says nothing about the land behind the beach.

The sand at the wave swings with El Niño.

The beach at the wave moves about −8.4 m per +1 °C of the El Niño index against the control beaches (95% range −14.7 to −4.4 m); the controls themselves move −1.6 to −0.8 m per °C. Past swings came back. The missing sand moves with El Niño, but the cause cannot yet be separated from local ones.

The armored Z6 stretch, at the north end of the cove past where the wave ends, has sat 20–29 m behind its neighbors every year since 2016, with no new step. A smaller effect could be hidden in the year-to-year scatter, and when the armor went in is not pinned down. The long record for each stretch is on the shoreline page.

In the El Niño months of 2023–24 and 2026 so far, the beach north-west of the point sat about 4 m narrower than in all other months since 2022, most of them La Niña months, and about 2 m narrower than in ordinary months, a gap too small to call on its own. The stretch at the point itself is left out of this count because a seasonal creek crosses it. The sea sat about 10 cm higher in those months, which on its own would move the waterline about 0.6 to 2.6 m depending on the beach slope, so between a sixth and two-thirds of the change could be water rather than lost sand.