In this study, we analyse the sensitivity of nadir viewing satellite observations in the visible range to freshly produced lightning NO<sub>x</sub>, i.e. for meteorological and (photo-) chemical conditions found in and around cumulonimbus clouds. For the first time, such a study is performed accounting for photo-chemistry, dynamics, and radiative transfer in a consistent way: A one week episode in the TOGA COARE/CEPEX region (Pacific) in December 1992 is simulated with a 3-D cloud resolving chemistry model. The simulated hydrometeor mixing ratios are fed into a Monte Carlo radiative transfer model to calculate box-Air Mass Factors (box-AMFs) for NO<sub>2</sub>. From these box-AMFs, together with model NO<sub>x</sub> profiles, slant columns of NO<sub>2</sub> (S<sup>NO<sub>2</sub></sup>), i.e. synthetic satellite measurements, are calculated and set in relation to the actual model NO<sub>x</sub> vertical column (V<sup>NO<sub>x</sub></sup>), yielding the "sensitivity" S<sup>NO<sub>2</sub></sup>/V<sup>NO<sub>x</sub></sup>. <br><br> From this study, we find a mean sensitivity of 0.46. NO<sub>x</sub> below the cloud bottom is mostly present as NO<sub>2</sub>, but shielded from the satellites' view, whereas NO<sub>x</sub> at the cloud top or above is shifted to NO due to high photolysis and low temperature, and hence not detectable from space. But a significant fraction of the lightning produced NO<sub>x</sub> in the middle part of the cloud is present as NO<sub>2</sub> and has a good visibility from space. Due to the resulting total sensitivity being quite high, nadir viewing satellites provide a valuable additional platform to quantify NO<sub>x</sub> production by lightning; strong lightning events over "clean" regions should be clearly detectable in satellite observations. Since the observed enhancement of NO<sub>2</sub> column densities over mesoscale convective systems are lower than expected for current estimates of NO<sub>x</sub> production per flash, satellite measurements can in particular constrain the upper bound of lightning NO<sub>x</sub> production estimates.