Cloud 9 Alert Guide

Siargao, Philippines · part of the Cloud 9 spot guide

Cloud 9 is forecast-only — the nearest buoy is well over a thousand kilometres away — so its alert is a model-swell alert, and the height below is an open-ocean reading. Note that the alerting swell can be a dangerous approaching typhoon.

The forecaster's checklist

1. 1.Hunt west-Pacific typhoons from August through November firing east-to-northeast long-period swell.
2. 2.Off-season, read the northeast monsoon swell, but remember the Amihan wind is onshore.
3. 3.Prioritize period — 13 to 16 seconds and up is what makes it barrel every wave.
4. 4.Run on models — there is no near buoy — using GFS-Wave via Windy plus Surfline, and surf the dawn or a southwest-offshore window.
5. 5.Cross-check PAGASA and JTWC, because the swell that lights it up may be a dangerous approaching typhoon; and surf it on a mid-to-high rising tide over the sharp reef.

Local winds & tide

Best wind: W–SW offshore (the SW Habagat is prime) — from 180° to 270° (S–W).

Tide-sensitive and best on a mid-to-high rising tide, when the sharp reef is covered; low tide exposes it. No tide series is modelled.

Dial it in