Is there a special relationship between emotions and populism? Academic and popular discussions of populism frequently suggest that this is the case, and that anger and anxiety in particular, are crucial explanatory factors for the continued appeal of populist parties. But despite the often-posited link between negative emotions and populism, few studies have explored this relationship empirically. This paper aims to fill this gap and answer three related questions: Firstly, to what extent is the relationship between negative affect and populist party support unique to these parties and do we observe differences between left and right-wing populism? Secondly, what is the temporal relationship between affect and populism? Do voters support populist parties because they are anxious or does support for these parties create these negative emotions? And finally, are populists angry, scared, or both? In other words, to what extent do we need to distinguish between specific types of negative affect, such as anger and anxiety, when discussing the emotional underpinnings of populism? Comparing panel data from Austria and Germany, this paper investigates the relationship between anger and anxiety on the one hand, and support for populist parties on the other. Using a random-intercept, autoregressive cross-lagged design, the paper has three findings. First of all, the reinforcing pattern of increased negative emotions and increased party support is unique to (right-wing) populists. Secondly, this relationship is self-reinforcing. While negative affect leads to greater support for right wing populist parties, the reverse relationship is more consistent and of larger magnitude. Negative emotions trigger populist support, but they are more important for maintaining it. Finally, it is important to distinguish between anger and anxiety. While only anxiety is consistent in its ability to trigger populist support, subsequently both anger and anxiety are increased.