Weekly water clarity report

US Coastal Water Clarity — Week of Sep 7-13, 2026

Published Sep 15, 2026

US coastal water clarity this week: 3 regions clearing, 1 region declining, 2 regions steady.

Regional clarity model read — feet01020304050Hawaii50.6 ftFlorida Keys & South Atlantic40.0 ftFlorida Gulf Coast20.8 ftSouthern California20.7 ftNortheast Atlantic15.7 ftMid-Atlantic & Gulf Coast15.5 ftimprovingstabledecliningno data

Regional reads

Florida Keys & South Atlantic 40.0 ft stable

Submarius's clarity model read Florida Keys & South Atlantic at 40.0 ft regional average; consistent with the prior week's read.

Florida Gulf Coast 20.8 ft stable

Submarius's clarity model read Florida Gulf Coast at 20.8 ft regional average; consistent with the prior week's read.

Southern California 20.7 ft +1.9 ft

Submarius's clarity model read Southern California at 20.7 ft regional average; up 1.9 ft vs the prior week's read.

Hawaii 50.6 ft +3.5 ft

Submarius's clarity model read Hawaii at 50.6 ft regional average; up 3.5 ft vs the prior week's read.

Northeast Atlantic 15.7 ft +1.6 ft

Submarius's clarity model read Northeast Atlantic at 15.7 ft regional average; up 1.6 ft vs the prior week's read.

Mid-Atlantic & Gulf Coast 15.5 ft -16.1 ft

Submarius's clarity model read Mid-Atlantic & Gulf Coast at 15.5 ft regional average; down 16.1 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 Sep 14, 2026 at 06:39 UTC. Subscribe via RSS.