The initial results of a weather radar coverage analysis in support of the Reduce Weather Impacts (RWI) Sensor RightSizing program are presented. The main impetus behind this study is to identify gaps in the radar network relative to the Next Generation Air Transportation System (NextGen) end-state performance requirements. Because detailed performance requirements are currently available only for super-density terminal airspace, we focused on this domain. We also analyzed, to a lesser extent, the contiguous United States (CONUS) airspace as an approximation to the en route airspace. Significant gaps were uncovered in the following requirement areas. (1) Vertical resolution. The current weather radar network (and any future radar network of reasonable cost) will not meet the 4D weather cube single authoritative source (4D WxSAS) vertical resolution requirements for both super-density terminal and en route airspace domains. (2) Vertical accuracy. Accurate determination of the radar beam height is difficult due to the natural variability of the vertical refractivitiy gradient in the atmosphere. (3) Update period for convective weather. The current weather radars have volume scan update periods that are substantially longer than the required times. (4) Horizontal resolution. This requirement is met in only some parts of the super-density terminal and en route airspaces (5) Low-altitude coverage. The current weather radars are generally spaced too far apart to provide seamless coverage of the boundary layer. (6) Overall terminal airspace weather radar coverage is significantly diminished due to terrain blockage at a handful of major airports.