<![CDATA[Rapidly varying marine weather requires onboard observations that combine measurement quality, spatial context, continuous data delivery, and clear operational interpretation. This study evaluates an Internet of Things (IoT)-based Smart Onboard Weather Station through controlled calibration, moving-vessel field comparison, preliminary data-continuity assessment, and exploratory usability evaluation. The platform is intended to support bridge officers during onboard weather monitoring and shore-based BMKG personnel reviewing vessel observations; the present usability sample represents the latter professional group. The system integrates a Campbell Scientific ClimaVUE sensor, CR1000X datalogger, GPS receiver, digital compass, camera, LTE/4G communication, time-series storage, and a web dashboard. Calibration across three to five set points produced near-linear responses for air temperature (R² = 0.999), relative humidity (R² = 0.995), atmospheric pressure (R² = 0.990), wind speed (R² = 0.999), and wind direction (R² = 0.990), together with parameter-specific correction and dispersion information. A seven-day deployment on the Merak–Bakauheni route from 21 to 27 December 2025 showed the strongest spatial coherence for atmospheric pressure and useful temporal agreement for air temperature, while wind speed produced the largest vessel-to-coastal differences. Data completeness reached 96.75%, representing preliminary operational data continuity under the tested conditions. The archived distance-summary dataset preserves interval-level statistics, while paired-observation counts fall outside the retained metadata and are carried as a reporting limitation. An exploratory SUS assessment with nine meteorological professionals produced a mean score of 81.39. The next readiness step is a controlled crewed pilot on a second vessel, with wind processing and bridge-user evaluation as the primary operational gates.]]>
