What is a key requirement regarding weather conditions when issuing a Convective SIGMET?

The correct choice highlights the necessity of maintaining Visual Flight Rules (VFR) when issuing a Convective SIGMET. A Convective Significant Meteorological Information (SIGMET) is an advisory issued by meteorological authorities to inform pilots of potentially hazardous weather conditions due to convective activity such as thunderstorms, turbulence, or severe icing.

When a Convective SIGMET is in effect, it indicates that adverse weather is occurring that could impact VFR operations. Pilots operating under VFR must maintain specific visibility and cloud clearance requirements to ensure safe flight. Therefore, knowing that VFR conditions must be maintained underscores the importance of situational awareness and adaptation to changing weather conditions. This requirement reinforces the need for pilots to have a clear understanding of both the current weather and forecasts, allowing them to adjust their flight paths or levels of operation accordingly to stay safe during flight.

In contrast, the option that discusses weather developing as forecasted does not directly relate to the issuance of a Convective SIGMET, nor does the specification concerning aircraft diversion or radar monitoring, which are not mandatory aspects within the context of issuing such advisories.