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USCG: Unexpected heavy weather dangers

The United States Coast Guard (USCG) has released Safety Alert 07-21 relating to the unexpected danger posed by weather at sea. 

The USCG notes: “Unexpected heavy weather events and rapid changes in weather have contributed to multiple notable and deadly marine casualties over the past several years. These casualties involved a wide range of vessels, including sailboats, passenger vessels, offshore vessels and recreational boats. While different size vessels normally operate in diverse geographical areas and different types of vessels may need to implement unique safeguards, there is a common theme – if you are not ready for heavy weather or rapid changes in weather, you and your vessel may suffer devastating consequences.

Heavy weather events or rapid changes in weather can be even more severe if you do not know about the approaching conditions. Operating on the water may provide a clear view of approaching weather, but it is not always indicative of the severity of a storm.

Although modern day forecasting has improved, and mariners and recreational boaters have the ability to receive updates and warnings through a wide variety of means, weather related maritime disasters continue to occur. This introduction of modern day technology into weather forecasting also increases the complexity in determining if the forecast applies to the geographical area where the vessel is actually operating.”

The capsized lift boat SEACOR POWER

To prepare for heavy weather events or rapid changes in weather, the Coast Guard recommends that all vessel owners, operators and mariners:

  • Ensure that your vessel is equipped with at least two different and reliable methods to obtain information about changing weather conditions;
  • Maintain a proper lookout at all times to recognize changing environmental conditions;
  • Ensure that one or more individuals on the vessel have the designated responsibility to check weather on a regular basis and share updates with others onboard. 
  • Understand your vessel’s operating limitations and key factors, e.g., vessel loading, down flooding points, profile and sail area, with respect to weather conditions;
  • Prepare for heavy weather events ahead of time;
  • Create an atmosphere of open communication onboard, so everyone feels comfortable discussing weather conditions and any related concerns.
  • If weather conditions start to deteriorate, take quick and decisive action to alter course or to abort an operation to protect human life. Build in a safety buffer that allocates time for storm preparation and evasion operations.

Members may wish to refer to:

Safety Event

Published: 25 November 2021
Download: IMCA SF 32/21

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