Design practices are often undervalued in climate service development. We combine a review of 55 operational web-based climate services with User Interface (UI) and User Experience (UX) design literature, using a systematic coding framework to assess how design practices are reported. The analysis identifies recurring gaps between recommended design methods and those documented in climate service development, including the near absence of formal usability testing (1 of 55 tools) and limited reporting on web accessibility (4 of 55). Projects mostly treat design as a secondary layer to refine conventional scientific visuals, overlooking core design workflow elements such as user research, iterative prototyping, and usability testing. We outline practical steps for integrating UI/UX design throughout the development process, helping teams plan design activities, work with designers, and manage expectations across development stages. Two case studies illustrate the workflow in practice. Climate and Water supports water managers assessing climate change impacts on water resources. POSUKHA provides drought forecasts for farmers. Together, they show that while design workflows can follow shared principles, visual and interaction solutions must remain tailored to specific user contexts. We show that UI/UX design is an end-to-end process to ensure usability, trust, and informed decision-making.