After the cold and dark of winter, river ice breakup represents a striking change for those living in and alongside northern rivers. For many communities, the promise of open water is accompanied by a risk of ice-jam flooding. Unfortunately, ice-jam floods are often more rapid, more severe, and more challenging to forecast than their open-water counterparts. Discharge forecasts alone do not provide enough information – forecasters must also consider the evolution of ice conditions and their effect on local discharge and water level. Reliable forecasting can improve ice-jam flood-readiness by giving decision-makers useful information on the timing and intensity of the upcoming breakup. We present a model framework for forecasting the timing and intensity of river ice breakup on large northern rivers and explore results for four sites: Dawson, YT (Yukon River), Old Crow, YT (Porcupine River), Ross River, YT (Pelly River), and Fort McMurray, AB (Athabasca River). Our approach seeks to balance physical representation with the needs and realities of operational, real-time flood forecasting. The models calculate an approximation of the forces driving and resisting breakup at each site using readily available data and observations. The forecasted timing of breakup corresponds to the time at which the driving force exceeds the resisting force. The forecasted magnitude of the forces at that time, meanwhile, indicates the potential severity of flooding.