A three-day precipitation event was simulated using Weather Research and Forecasting (WRF) model coupled with a Spectral Bin Microphysical (SBM) scheme. On January 6th, a synoptic frontal system passed through NYS, and was followed by a lake effect event that lasted to January 8th, 2014. With a focus of aerosol indirect effect over the complex terrain of NYS, three sensitivity studies on this event were conducted: 1) a Control Case with background aerosol of low concentration, 2) an IN Case with doubled ice nuclei (IN) concentration, and 3) a CCN Case with tripled cloud condensate nuclei (CCN) number than the Control Case. In the frontal system, the ice-to-liquid partition within the cloud and in the surface precipitation was strongly affected by extra INs and CCNs. For the lake effect event with a much colder atmosphere, extra IN had large impact on the cloud by forming more ice crystals directly over the lake and invigorating the vertical motion within the lake effect cloud band, resulting in taller and narrower cloud band as well as increased precipitation over the downwind Tug Hill. Whereas the more numerous small cloud droplets and lower rimming efficiency associated with extra CCNs buffered the increased ice collection rate, resulting in a similar convection intensity and surface precipitation to the Control Case.