Frost early in the growing season affects many crops and plant species. In Norway, warm early springs can trigger early flowering, followed by cold spells causing frost damage. Although warming extends the growing season, frost risk may increase at its start or end. At present, the early-season risk is highest in lowland South Norway, especially the southeast, and has increased most along the west coast. Future projections indicate an increasing risk along the coast, but decreasing risk inland.

FEWSs are difficult to implement in shared river basins because institutional fragmentation and decision-making asymmetries. Using the transboundary expansion of the SLAPIS FEWS between Niger and Burkina Faso, this study shows how an existing co-production framework can be operationally adapted to address these challenges. The paper identifies practical implementation requirements for transboundary climate services and highlights priorities for future research on evaluating their added value.