Figure 3. Global 500-mb geopotential height ACC (top) and RMSE (bottom, m) difference from the contemporary GFS as a function of lead time (instantaneous at 00Z each day after initialization) for each version of the 13-km SHiELD. Gray shading is the 95% confidence interval. Each version of SHiELD is evaluated with two years of 10-day hindcasts initialized at 00Z every five days, for a total of 144 cases per version. See Table 1 for the time periods being compared here.