Quick answer: Sargassum is floating brown seaweed that sometimes washes onto St Croix beaches, mainly in summer. Amounts change week to week with wind and currents. Use the live forecast maps below to check what may arrive in the next few days and pick beaches with less seaweed.
St Croix can get Sargassum at times (especially in summer). It’s part of a wider Caribbean pattern that can also affect Florida and Mexico. A little planning can help prevent it from ruining your holiday. Here’s some useful information about what causes Sargassum, tips to help avoid Sargassum, as well as the latest Sargassum maps in the US Virgin Islands. Get fresh updates about the St Croix Sargassum 2026 situation as you plan your trip.
Sargassum in St Croix can change week to week based on wind and currents. Check the live forecast maps on this page (especially the last 7-14 days) and then confirm with the live beach webcams below. Even during peak season, some St Croix beaches can stay mostly clear.
Sargassum season in St Croix usually peaks in summer, most often from June through September. Some years are lighter and some are heavier. Conditions can also shift quickly after wind changes or storms.
The worst months for sargassum in St Croix are usually June, July, and August. September can also be impacted depending on weather patterns. May is often the transition month when larger arrivals may begin.
The side of St Croix that is downwind can get more sargassum at a given time. That means one coastline can be affected while another is mostly clear. Because wind direction changes, the live forecast map is more reliable than general rules.
Seagrass grows naturally underwater in some St Croix bays and is not considered a nuisance. It often supports fish and turtles and can improve snorkeling. Sargassum floats on the surface, washes onto beaches, and can pile up and decay in large amounts.
Sargassum Seaweed 2026 Forecast Map
How to read the sargassum forecast map:
- Check the last 7-14 days to see the direction of movement
- Use the 3-day forecast to estimate near-term arrivals
- Wind shifts can move sargassum to different coasts quickly
- After storms, conditions may change within 24-48 hours
Check the latest sargassum 2026 update map for the whole Caribbean including St Croix & St Thomas USVI. Zoom in to any location, watch the past 2 weeks and zoom out to see what might arrive in the next 2 weeks.
Seeing recent flows can help increase your chances of finding sargassum-free beaches or at least beaches without sargassum in massive amounts.
It may take 15 seconds to load because it’s a lot of data.
Typical Sargassum Season
| Month | Typical Sargassum Risk (St Croix) | What to Expect | Best Planning Tip |
|---|---|---|---|
| January | Low | Usually minimal sargassum | Pick beaches based on wind and you’ll usually be fine |
| February | Low | Typically low risk | Great month for clear water and snorkeling |
| March | Low | Usually low risk | Check the live map only if you see unusual reports |
| April | Low to Medium | Can start increasing | If you’re sensitive to seaweed, prioritize north/west beaches |
| May | Medium | First larger arrivals possible | Use the 3-day map before choosing your beach each day |
| June | High | Peak season begins | Expect variability – some beaches can be clean, others impacted |
| July | High | Often heavy sargassum weeks | Avoid planning a trip around one perfect beach |
| August | High | Peak season continues | Focus on beaches that are clean that week, not the best overall |
| September | Medium to High | Can remain significant | Storms can shift conditions quickly in 24-48 hours |
| October | Medium | Often improving | Conditions usually start easing, but not guaranteed |
| November | Low to Medium | Typically much less | Great shoulder month with lower seaweed risk |
| December | Low | Usually minimal | Good month for calm beach conditions |
Best Sargassum-free beaches in St Croix in 2026
While never guaranteed, your best shot for sargassum-free beaches is the North Shore and the West End. Because Sargassum flows from the southeast, the South Shore & East End get hit the hardest.
Here are some useful tips to prevent Sargassum from spoiling your Virgin Island vacation. A little planning and flexibility can go a long way.
How to Keep Seaweed From Ruining Your Holiday
- Travel between November and May: Sargassum blooms are greatest during the summer when water temperatures are higher. Winter & spring months see much less Sargassum, or none at all. Click here to see the sargassum season.
- Get a rental car: having a car gives you great flexibility to choose between beaches. So if the beach where you’re staying has a Sargassum problem you can easily spend your days at other Sargassum-free beaches.
- Stay on the West End or North Shore: as said earlier, these sides of the island experiences the lowest levels of St Croix Sargassum due to the directional flows of the algae and ocean currents.
- Focus on land-based activities: there are so many amazing land-based activities on St Croix that many people overlook because of our great beaches. Try ziplining, a off-road jeep tour, horseback riding, visiting historical sites, etc.
- Keep perspective: Sargassum is nature in action, and while it occasionally may create some unpleasantness and odor, don’t let it hijack your holiday. Take it in stride, relax, enjoy another rum punch, and view it as a chance to take in all the many other wonderful pleasures of St Croix beyond the beach. When life gives you lemons, ask for tequila & salt.
Current 2026 Sargassum Seaweed Conditions in St Croix US Virgin Islands
The best way to check the latest St Croix Sargassum situation is on the Sargassum Map above and with the real-time live St Croix beach webcams below. These seaweed beach cams will help you sargassum-free beaches which are available TODAY!
St Croix Sargassum 2026 Forecast
Sargassum seaweed may or may not return to St Croix & St Thomas in summer 2026 It’s impossible to predict if it will appear, and if it will be a serious problem or minor nuisance. As stated above, there are always plenty of sargassum-free beaches in St Croix to visit so don’t let it affect your vacation planning. Remember, many other locations get hit a lot worse!
St Thomas Sargassum 2026 Forecast Report
What’s the current St Thomas Sargassum seaweed situation? Where can I find St Thomas Beaches without Sargassum Seaweed?
Click on the live beach cams to find the current St Thomas sargassum 2026 updates.
What’s the Margaritaville St Thomas seaweed situation like? While there are no live webcams at the resort, it’s best to check nearby beach webcams to get some idea if it is a problem or not.
St John sargassum 2026 forecast report
Looking for St John beaches without Sargassum seaweed? Then click on live webcams below to see current St John sargassum 2026 levels in the US Virgin Islands.
Here’s also a source for St John Sargassum 2026 weekly updates: https://explorestj.com/sargassum/
3-day Sargassum Forecast for USVI (St Croix & St Thomas)
Click on the map below for real-time satellite Sargassum seaweed forecast for St Croix & St Thomas.
You can also visit the Satellite-based Sargassum Watch System (SaWS) site with real-time sat photos but you’ll need some technical background to interpret the data.
Caribbean Sargassum Season 2026
The “Caribbean Sargassum seaweed season” usually peaks in summer, from June until September. The sargassum season for Cancun, Mexico, Florida, Punta Cana, and the whole Caribbean can be easily visualized in the below video:
NOAA Sargassum seaweed map in 2026
A final and solid resource for real-time sargassum seaweed maps is the National Oceanic & Atmospheric Administration’s Ocean Viewer Satellite Seaweed Detection and Monitoring From Space. Here you can find satellite maps and 2026 forecasts of sargassum levels in Florida, Cancun, Mexico, the Caribbean, and of course the US Virgin Islands, as well as sargassum forecasts for 3-14 days. A very valuable resource.
Sargassum 2026 update news
2025 Could See a Surge in Sargassum Seaweed Across the Region