The upward trend in atmospheric carbon dioxide is accompanied by a trend in the carbonate system, oxygen concentrations, and temperatures of the global ocean, but in coastal environments, local and regional processes can modulate or exacerbate these trends. Coastal and regional processes can occur on spatial scales that are not well represented in global climate models (GCMs), but the relative importance of these processes to modification on climate timescales for coastal trends remains understudied. Using downscaled simulations to forecast (seasonal) and project future (~2100) ocean health conditions off the west and east coast of the U.S under SSP5-8.5, modification by coastal or regional processes of ocean health metrics is simulated. The importance of local processing is established for some variables -including carbonate system variables – more than others but forecast and projections are possible at local scales. Forecasts on any timescale need to be tailored to the needs of stakeholders. Indices based on carbonate system conditions specific to Dungeness crab have been co-produced with state and tribal managers and while they prove skillful historically, the forecasts of ocean conditions provide that skill. On the east coast, projections of scallop growth provide a potentially useful link to downscaled projections to management and require ocean conditions of benthic conditions that are distinctly different than the global projections. The results suggest projections that resolve coastal processes are necessary for adequate representation of the magnitude of projected change in carbon stressors in both systems, and that proactive adaptive strategies informed by robust science can be established, prioritized, and implemented to aid management in sustaining marine resources.