Which sources provide the most accurate information on current and forecast icing conditions?

The sources that provide the most accurate information on current and forecast icing conditions are indeed PIREPs, Area Forecast, and the Freezing Level Chart.

PIREPs (Pilot Reports) are invaluable as they offer real-time observations of icing conditions encountered during flights, providing firsthand accounts of turbulence, icing, and cloud information. The Area Forecast presents a broad overview of weather conditions, including anticipated icing in defined regions, giving dispatchers critical insights into expected atmospheric conditions.

The Freezing Level Chart details the altitude at which the temperature is at or below freezing, which is essential for understanding the potential for icing. This chart helps dispatchers identify where icing may occur based on the specified freezing levels in relation to the aircraft's flight path.

While other sources such as the Low-level Sig Weather Prog Chart, RADATs, AIRMET Zulu, and additional forecasting tools do provide useful weather information, they may not specifically focus on icing conditions to the same degree as the trio of PIREPs, Area Forecast, and the Freezing Level Chart. Therefore, these three selected sources are the most reliable for assessing current and forecast icing conditions.