Under what weather conditions is the ILS Hold Short in effect?

The condition described as "WX less than 800-2" refers specifically to weather scenarios where visibility is below 800 meters (approximately 0.5 miles) and the cloud ceiling is below 2000 feet. The Instrument Landing System (ILS) Hold Short procedure is implemented under such conditions to ensure that aircraft do not proceed onto the active runway when visibility and cloud cover create a hazardous scenario, impacting safe operations during instrument approaches.

In essence, these specific weather criteria establish the threshold for when hold short instructions must be adhered to for safety reasons. This reflects the need for optimal visibility and cloud clearances during aircraft operations, especially under instrument flight rules (IFR). Any other conditions listed, such as fog, thunderstorms, or general visibility below 1000 feet, do not reflect the precise criteria set for the ILS Hold Short, illustrating the importance of adhering to specific, standardized weather parameters in aviation safety practices.