Changes of the meridional overturning circulation (MOC) due to surface heat flux variability related to the North Atlantic Oscillation (NAO) are analyzed in various ocean models, i.e., eddying and non-eddying cases. A prime signature of the forcing is variability of the winter-time convection in the Labrador Sea. The associated changes in the strength of the MOC near the subpolar front (45¿N) are closely related to the NAO-index, leading MOC anomalies by about 2--3 years in both the eddying and non-eddying simulation. Further south the speed of the meridional signal propagation depends on model resolution. With lower resolution (non-eddying case, 4/3¿ resolution) the MOC signal propagates equatorward with a mean speed of about 0.6 cm/s, similar as spreading rates of passive tracer anomalies. Eddy-permitting experiments (1/3¿) show a significantly faster propagation, with speeds corresponding to boundary waves, thus leading to an almost in-phase variation of the MOC transport over the subtropical to subpolar North Atlantic.