“…There have been substantial improvements in NWP forecasts since the 1990's, arising from improved data assimilation and better observations (e.g., Barker et al, 2004;Snyder and Zhang, 2003;Huang et al, 2009;Sun et al, 2010;Xiao et al, 2007;Zhang et al, 2014). For example, as one of the most used global models at the Meteorological Service of New Zealand (MetService), the Global Forecasting System (GFS) from the National Centers for Environmental Prediction (NCEP) has shown noticeable improvements, including in QPF (e.g., Wang et al, 2013), after the introduction of the hybrid ensemble variational assimilation scheme in 2012.…”