Hiwas
From Wikipedia, the free encyclopedia
HIWAS (Hazardous Inflight Weather Advisory Service) is a continuous broadcast of a summary of hazardous weather information which is transmitted over selected VORs/navaids. This hazardous weather includes AIRMETs, SIGMETs, Convective SIGMETs, and urgent PIREPs.
The presence of HIWAS information on a navaid is indicated on a sectional by an "H" in the upper-right corner of the box surrounding the navaid frequency.[1]