Stokes profiles and atmospheric models from an umbral flash. Top panels: Stokes I (panel a) and Stokes V (panel b) profiles. Bottom panels: vertical stratification of the velocity (panel c), temperature (panel d), and magnetic field (panel e) as a function of the optical depth (bottom axis) and geometrical height (top axis). In all panels, the red lines illustrate the quantities directly obtained from the numerical simulation, whereas black and gray lines are the results obtained from inversions with one or three velocity nodes, respectively.