Marine construction operations are inherently challenging due to the harsh and unpredictable marine environments in which they take place. The study focuses on the specific challenge posed by adverse weather conditions, which often lead to downtime, impeding the progress of marine construction operations. A hypothetical project operation at an ongoing project site, the Vizhinjam International Seaport (VISL), Kerala on the west coast of India, is considered a case study. The assumed limiting wave conditions for the operations are a wave period (Tav) of 10 s and a significant wave height (HS) of less than two meters. The total duration of the operation is estimated to be 10 h. The analysis was carried out to identify a favorable weather window for executing the particular operation, utilizing the wave scatter approach, which is a joint probability method. For this purpose, historical wave height data spanning from 2019 to 2021 is analyzed to calculate the workability percentage for the selected operation. The results reveal a significant downtime (approximately 60%) between June and September, primarily due to unfavorable weather conditions, making these months unsuitable for conducting the operation. However, the remaining months in the calendar year exhibit sufficient workability percentages. Notably, January, February, and April demonstrate the highest workability percentages, making them the most favorable months for executing the operation. The study's findings shed light on the difficulties of maritime construction operations and highlight the need to include downtime analysis into marine project scheduling and planning. By conducting such studies one can optimize the scheduling decisions, mitigate risks, and enhance the operational efficiency in marine construction projects.