Small craft advisories do not apply to specific sizes of boats; instead, these warnings refer to adverse weather events and sea conditions such as high waves and wind that may affect the safety and navigation capabilities of small-sized boats. The National Weather Service (NWS) issues Small Craft Advisories (SCAs) to warn operators and crew members of water vessels when conditions may pose threats to safety and travel. Rather than preventing certain boats from taking to affected waters during foul conditions, the NWS advises all boats potentially affected by the specific advisory criteria to stay ashore.
The NWS identifies six distinct geographical regions across the United States that affect nautical travelers. The Eastern region extends along the northeastern seaboard from Maine to the Carolinas, and includes Lake Erie and Lake Ontario. This region generally has winds in the range of 25-33 knots; wind speeds exceeding this number trigger the NWS to issue a Small Craft Advisory. Additionally, waves extending over 7 feet alert the NWS to issue Small Craft Advisories; waves in this region typically peak at 5 to 7 feet. The second region includes the geographical area between Minnesota and Ohio. Small Craft Advisories arise when winds exceed 33 knots, as ordinary wind speeds fall between 22 and 33 knots. Region 3, which includes southern waters and waters in the Caribbean, has similar conditions. Regions 4 and 5 (the Pacific coastline) have similar wind speeds to those in the northeastern states and midwest, but seas here routinely reach up to 10 feet. Therefore, the NWS issues Small Craft Advisories for the Pacific regions when waves exceed 10 feet.