This study assesses weather windows and weather-related downtime for the installation and maintenance activities of the First Offshore Wind Project of India (FOWPI) in the Gulf of Khambhat, Gujarat. It analyses wind speed and significant wave height using five years of hindcast metocean data to determine suitable operating periods for offshore transportation, installation and maintenance activities. The study evaluates different weather thresholds and operation reference periods, providing monthly and annual probabilities of weather windows and downtime. The results support offshore installation planning, accessibility, safety and selection of appropriate service vessels, while recommending that the analysis be updated when long-term site-specific wind measurements become available.