High-voltage double-circuit transmission lines are vital for grid capacity but create structural dependencies prone to Common Cause Failures (CCF). This research investigates the vulnerability of shared infrastructure under extreme wind stress, shifting from static failure models to a dynamic resilience simulator. The study specifically addresses the ’degraded state’ where one circuit has failed while the other remains operational. The methodology advances the VAFFEL approach by integrating a 4-state Continuous-Time Markov Chain framework. Utilizing the MERIDA HRES meteorological dataset, the framework was applied to the Sicilian 220/380 kV grid, exposed to extreme winds during the 2012-2020 time period. A virtual failure history was synthesized to anchor simulations to real-world meteorological stressors.