Winter windstorms associated with intense extra-tropical cyclones (including transitioning tropical cyclones) are a major hazard in the US Northeast in the contemporary climate. Questions remain regarding how such events may evolve in the future and specifically which tools and approaches are best suited to making robust projections. Within the HyperFACETS project we are taking a four-pronged approach, producing and analyzing; (i) Storyline-PGW simulations performed at convection permitting scales, (ii) Transient, moderate resolution regional simulations performed within multiple ESMs, (iii) ESM large ensembles and most recently (iv) High resolution simulations of storylines for transitioning tropical cyclones (Hurricanes Irene and Sandy) performed using atmosphere-only WRF and fully coupled atmosphere-wave-ocean simulations with COAWST. Storylines in which only thermodynamical perturbations are applied suggest any change in the threat posed by synoptic-scale winter windstorms are likely to be associated with changes in accompanying precipitation with little evidence of a thermodynamic feedback to the cyclone intensity and dynamics. Although few historical storylines derive from transitioning tropical cyclones, some ESMs when downscaled using WRF imply a possible increase in the number of transitioning tropical cyclones entering the Northeast causing an increase in mean windstorm intensity. Finally, the large ensemble analysis suggests a critical role of internal climate modes in dictating individual member behavior (e.g. frequency of windstorms). While these results are thus frustratingly inconsistent in terms of the end-of-century geophysical hazard presented by windstorms in the northeastern USA, they show the value of integrating multiple lines of evidence in assessing future climate risks.