What to expect for water quality, rainfall, and ocean conditions
Transitional months see variable rainfall. The reef-protected lagoon at Ala Moana can trap contaminants from urban runoff. Monitor conditions after rain events, especially near the Waikiki end of the beach.
October marks the wet season transition. Rainfall increases to about 2 inches. The first significant storms can flush accumulated urban contaminants into the lagoon from surrounding drainage.
Fall brings transitional conditions. The lagoon stays protected by the reef. South-shore surf is generally small. Water temperature begins cooling from around 79°F. Occasional east swells create some chop.
Moderate to low. Fall shoulder season offers fewer tourists while conditions remain good. This is one of the best value periods for visiting Hawaii.
The Hawaii Department of Health recommends staying out of the ocean for at least 72 hours after heavy rain. In october, this is especially important as wet-season storms can produce heavy rainfall and significant runoff.
When conditions are clear, Ala Moana Beach has excellent ocean activities. Check the water quality above, then book with confidence.
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Safe to Swim Hawaii provides water quality information based on publicly available DOH data and seasonal patterns. This is not medical or safety advice. Always check current conditions, obey posted signs, and use your own judgment before entering the ocean. Privacy Policy
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii Department of Health or any government agency. Water quality ratings are estimates based on publicly available testing data and geographic analysis. They are not real-time measurements and may not reflect current conditions.
Always verify current water quality conditions with the Hawaii DOH Clean Water Branch before entering the water.
When in doubt, don't go out. 🤙