The Development and Evolution of Two Atmospheric Rivers in Proximity to Western North Pacific Tropical Cyclones in October 2010
The development of the two ARs occurred in association with decreasing integrated water vapor (IWV) values in an environment characterized by the transport of water vapor along the AR corridor from TC source regions, troposphere-deep air parcel ascent, and large precipitation rates. The development of the two ARs occurred within the equatorward entrance region of an intensifying North Pacific jet stream (NPJ) and evolved similar to mature predecessor rain events (PRE) ahead of TCs. The subsequent evolution of the two ARs occurred in association with constant IWV values in an environment characterized by the transport of water vapor along the AR corridor from extratropical and subtropical source regions, strong frontogenesis, large precipitation rates and large amounts of IWV flux convergence. An AR water vapor budget demonstrates that decreases in IWV via precipitation along an AR may be offset by the horizontal aggregation of water vapor along the AR via IWV flux convergence in the presence of frontogenesis. In the present study, the results indicate that the PRE-like development of the ARs may have facilitated the intensification of the NPJ and generation of strong frontogenesis that supported the subsequent maintenance of the ARs prior to landfall.