Weekly water clarity report

US Coastal Water Clarity — Week of Oct 12-18, 2026

Published Oct 20, 2026

US coastal water clarity this week: 1 region clearing, 1 region declining, 4 regions steady.

Regional clarity model read — feet01020304050Hawaii53.4 ftFlorida Keys & South Atlantic30.7 ftMid-Atlantic & Gulf Coast26.5 ftSouthern California21.6 ftFlorida Gulf Coast17.3 ftNortheast Atlantic11.0 ftimprovingstabledecliningno comparisonno data

Regional reads

Florida Keys & South Atlantic 30.7 ft -2.6 ft

Submarius's clarity model read Florida Keys & South Atlantic at 30.7 ft regional average; down 2.6 ft vs the prior week's read.

Florida Gulf Coast 17.3 ft stable

Submarius's clarity model read Florida Gulf Coast at 17.3 ft regional average; consistent with the prior week's read.

Southern California 21.6 ft stable

Submarius's clarity model read Southern California at 21.6 ft regional average; consistent with the prior week's read.

Hawaii 53.4 ft stable

Submarius's clarity model read Hawaii at 53.4 ft regional average; consistent with the prior week's read.

Northeast Atlantic 11.0 ft stable

Submarius's clarity model read Northeast Atlantic at 11.0 ft regional average; consistent with the prior week's read.

Mid-Atlantic & Gulf Coast 26.5 ft +2.5 ft

Submarius's clarity model read Mid-Atlantic & Gulf Coast at 26.5 ft regional average; up 2.5 ft vs the prior week's read.

How the model works

Submarius estimates horizontal underwater visibility for any coastal point. It starts from that location's typical clarity for the time of year, built from in water measurements and satellite ocean color, then subtracts what changes day to day: wave stirring judged against depth and bottom type, river and runoff plumes, and tide driven water movement. Each estimate shows its data sources and how fresh they are. The underlying optics draw on Lee et al. 2015. See the methodology overview, the plain English conditions guide, and the glossary for the full picture.

Per-location and arbitrary-lat/lon clarity reads are available in the Submarius app. This weekly report publishes only regional aggregates so the model's recipe stays protected while the outcomes stay public.

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Model read taken Oct 19, 2026 at 06:40 UTC. Subscribe via RSS.