Head to head editorial

St. Thomas vs St. John vs St. Croix: sargassum compared

No clear winner on geography: the shores this atlas tracks on St. Thomas, St. John, and St. Croix all face generally north, so the live cards and cameras should make this call.

The reasoning

Why the map says what it says

With the orientations this close, the differences that decide your beach day are local: each national-park pocket beach on St. John can have its own morning, and the south and east coasts of St. Croix face different water than the Christiansted shore rated below. Compare the three cards, then open a cam on the island you are leaning toward.

Editorial judgment based on coast orientation; the cards below are the data. Seaweed lands mostly on coasts facing the open Atlantic (NOAA CoastWatch FAQ). Reviewed 2026-09-01.

Right now

Current risk level, side by side satellite-derived

Both measured from NOAA's update of . Each card rates one specific stretch of coast; open a destination for the full picture.

The record

September, five years back satellite-derived

Raw satellite floating-algae detections near each coast for this month in each of the past five years (brighter orange and red = stronger signal). These are detections, not risk ratings: clouds and glare can hide algae, offshore mats do not always land, and the nearshore strip is blanked where the signal is unreliable. Click any map for that month's full Caribbean view.

Making the call

How to decide

  1. Read the cards above, including the full mix of levels, not just the headline.
  2. Open a beach cam for each contender if one exists; nothing beats looking.
  3. Ask each hotel for a same-day photo of its swimming beach.
  4. Remember the atlas rates coastlines, not resorts: one cove can beat its neighbor on the same morning.

More head-to-heads on the compare page, or build a shortlist from scratch with where beaches stay clearer.