Two studies examined the dynamics and predictors of momentary creative activity among adults. Study 1 (N = 74) applied the experience sampling methodology (ESM) to investigate the likelihood of engaging in creative activity and explain its variability using both within-person predictors (experienced emotions) and between person-predictors (personality and creative activity). This study also demonstrated that the likelihood of momentary creative activity during a random week at the age 52 is predicted by participants’ intelligence measured 4 decades ago. Study 2 extended these findings: In a 2-week-long diary study, participants (N = 433) reported their everyday creative behaviors and activity in the spheres related to arts (painting, composing music, writing), science (writing scientific articles, solving technical problems), and everyday functioning (cooking, blogging). Active positive emotions generally predicted day-to-day variability of creative behavior, whereas the role of individual-differences was more complex and domain-specific.