Climate variability is reshaping infectious disease risk through ecological, environmental, social, and health-system pathways. However, its operational implications remain insufficiently defined in fragile and conflict-affected settings. Somalia is a critical case because recurrent droughts and floods intersect with displacement, food insecurity, weak water and sanitation infrastructure, disrupted immunisation, livestock dependence, and constrained health-system capacity. This narrative review synthesises evidence on climate-sensitive infectious disease risks in Somalia, examines existing surveillance and early warning systems, identifies policy and implementation gaps, and proposes priorities for a climate-informed surveillance-to-action model for infectious disease control. The review distinguishes directly climate-sensitive infections, including cholera, malaria, dengue, and Rift Valley fever, from indirectly climate-amplified vaccine-preventable diseases, including measles, diphtheria, and polio. While Somalia has important surveillance and early warning assets, including EWARN, IDSRS/DHIS2, FEWS NET, FSNAU intelligence, WASH monitoring, livestock signals, and community-based reporting, these streams remain insufficiently integrated into district-level risk assessment and pre-financed preparedness action. Therefore, the central challenge is not the absence of warning signals but the failure to convert them into timely, disease-specific, and accountable responses. We propose a surveillance-to-action framework based on multisource signal detection, integrated district risk assessment, disease-specific trigger decisions, early preparedness actions, and feedback, accountability, and learning. Closing Somalia's warning-to-action gap requires pre-agreed disease-specific triggers, One Health coordination, flexible anticipatory financing, strengthened district surveillance capacity, and equity-centred outreach to internally displaced persons, pastoralist and nomadic communities, zero-dose children, malnourished populations, and hard-to-reach areas. Climate-informed surveillance should be understood not merely as better data collection but as an anticipatory public health function designed to act before climate shocks become infectious disease emergencies.