This study tested dyadic processes of relational turbulence theory (RTT) in heterosexual marriages. We tested propositions 1, 2, and 5 of RTT, which propose that uncertainty about the marriage biases cognitive appraisals, and that interference from a partner heightens negative emotions, both of which culminate in relational turbulence for spouses. Guided by these propositions, husbands' and wives' (N = 510; 255 marital dyads) dyadic cognitive and emotional processes were estimated using the actor‐partner interdependence mediation model. Consistent with theoretical propositions, we found evidence for actor‐actor indirect effects; for both husbands and wives (a) the effect of spouses' relationship uncertainty on their own relational turbulence was mediated by their own biased cognitive appraisals, and (b) the effect of spouses' experienced interference on their own relational turbulence was mediated by their own anger from communicating in the marriage. However, controlling for actor‐actor indirect effects, partner‐defined processes (i.e., actor‐partner and partner‐actor indirect effects) uniquely explained husbands' and wives' relational turbulence.