What uniquely identifies NAVAIDs that provide HIWAS broadcasts?

NAVAIDs that provide Hazardous Inflight Weather Advisory Service (HIWAS) broadcasts are uniquely identified by a blue filled-in circle with a white "H." This symbol is specifically used to denote locations where HIWAS is available, making it easy for pilots to identify these critical advisory services on aeronautical charts.

The intent behind this designation is to enhance pilot awareness and ensure they have access to vital weather information during flight operations. The visual representation provided by the blue filled-in circle with a white "H" serves as a clear and standardized way for aviators to recognize NAVAIDs that contribute to safety by broadcasting real-time weather information and other pertinent advisories.

Other potential identifiers, such as frequency markings or color codes, do not convey the specific relationship to HIWAS service. Consequently, the blue filled-in circle with a white "H" remains the defining characteristic for these NAVAIDs, ensuring standardized communication and understanding within aviation operations.