Small Craft Advisory for Hazardous Seas

(SCAHS) - An advisory issued by coastal and Great Lakes Weather Forecast Offices (WFO). This advisory may be issued within the Coastal Waters Forecast or Nearshore Marine Forecast products. This advisory may be issued when wind speeds are lower than small craft advisory criteria, yet waves or seas are potentially hazardous due to wave period, steepness, or swell direction. Thresholds governing the issuance of Small Craft Advisories for Hazardous Seas are specific to geographic areas.

• Eastern (ME..SC, Lake Erie, Lake Ontario) - Seas or waves 5 to 7 feet and greater, area dependent.
• Central (MN..OH) - Seas or waves greater than 4 feet
• Southern (GA..TX and Caribbean) - Seas 7 feet or greater that are expected for more than 2 hours.
• Western (WA..CA) - Seas 10 feet or greater; or wave steepness values exceeding local criteria.
• Alaska (AK) - Seas or wave conditions deemed locally significant, based on user needs, and should be no lower than 8 feet.
• Hawaii (HI), Samoa - Seas 10 feet or greater.
• Guam and the Northern Mariana Islands - Combined seas of 10 feet or more.