First published Oct 21, 2026, 3:15:15 AM UTC · Last updated Oct 21, 2026, 3:15:15 AM UTC

Coastal and marine hazards

Special Marine Warning issued October 20 at 11:09PM AST until October 21 at 12:30AM AST by NWS San Juan PR

Reported by U.S. National Weather Service Alerts NWS

The National Weather Service in San Juan issued a marine warning for Atlantic waters of Puerto Rico and the U.S. Virgin Islands after radar indicated a severe thunderstorm capable of producing waterspouts. The warning instructed boaters to seek safe harbor immediately; additional details were not included in the source data received by Planet Briefing.

At a glance

Affected location: Atlantic waters of Puerto Rico and the U.S. Virgin Islands

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Why it matters

The source directs boaters in the affected waters to seek safe harbor immediately.

Location

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Generated scores

Scores are based on the cited reporting and use a 1–10 scale. Read the methodology.

Confidence: 8/10How certain the assessment is based on the clarity and evidence in the cited reporting.
Geographic reach: 1/10How widely the event reaches, from a local area (1) to worldwide impact (10).
Global importance: 2/10The event's broader significance, from limited importance (1) to major global importance (10).
Impact magnitude: 3/10The scale or severity of the real-world impact, from minor (1) to extreme (10).
Urgency: 9/10How time-sensitive the event is, from low urgency (1) to immediate attention needed (10).

Primary official sources

U.S. National Weather Service Alerts NWS Special Marine Warning issued October 20 at 11:09PM AST until October 21 at 12:30AM AST by NWS San Juan PR

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