According to the cognitive model of suicide, interactions between hopelessness and attentional biases toward suicidal information create a narrowed attentional focus on suicide as a viable solution, particularly in the presence of life stress, leading to increased suicide risk. This study used a dynamic systems approach to examine the short-term temporal patterns between stress, hopelessness, suicide-specific rumination, and suicidal intent. Adults (N = 237; M = 27.12 years; 62% cisgender women; 87% White/European American) with elevated suicidal ideation completed ecological momentary assessments six times a day for 14 days. A multilevel model approach informed by dynamic systems theory was used to simultaneously assess stable and dynamic temporal processes underlying perceived stress, hopelessness, suicide-specific rumination, and suicidal intent. Each variable demonstrated temporal stability. In support of the cognitive model of suicide, we observed (1) a reciprocal relationship between stress and hopelessness such that stress and hopelessness amplified each other (early-stage processes), and (2) reinforcing loops such that hopelessness, suicide-specific rumination, and suicidal intent amplified each other (later-stage processes). A dynamic systems modeling approach underscored the negative impact of a perpetuating cycle of suicide-specific rumination, deepening hopelessness, and escalating suicidal intent on increasing suicide risk, which may be targets for intervention.