The amplitude of coupled noise is often used in estimating the crosstalk effect. Coupling noise-induced delay measures the impact of crosstalk on circuit performance. Efficient computation of worst case noise-induced delays are essential, because such calculations are performed a huge number of times during timing analysis. In this paper we analyze the problem of crosstalk noise-induced delay in one logic stage. We observe that the popular method of crosstalk delay computation based on superposition of the victim?s switching waveform and the noise waveform determined when the victim is quiet, produces an underestimation of delay. To capture the crosstalk noise-induced delay, we introduce the concept of dynamic coupling noise waveform. We propose a method of synthesizing the dynamic noise waveform and using it to estimate the delay change.