This study utilized a two-phase user experiment to explore people's perceptual and cognitive states interacting with the COVID-19 dashboard to obtain outbreak information. Specifically, 27 participants were assigned to interact with this dashboard with different color arrangements and performed image-memory, search, and browse visualization tasks sequentially. We found that the participants expected to obtain both global pandemic trends and single region/date statuses from the dashboard to help them grasp important information in the shortest possible time. They also allocated their attention differently to the dashboard's content areas to match their individual visual movement and reading logics. Our participants indicated that the pandemic data visualization dashboard should use a principal-color selection that is alarming but without causing panic. In the study's second phase, an eye-tracking experiment, it was found that the participants' actual eye paths deviated from our expectations: clustering around headings and text, rather than on visualized charts or graphs as anticipated. Based on these findings, we provide design implications for builders of future data-visualization and disaster dashboards.