Structure of the visible hemisphere of WASP-121b as a function of phase from the solar composition SPARC/MITgcm model. α = 0 is the dayside as seen during secondary eclipse and α = −180 is the nightside as seen during transit. The first two rows show temperature and pressure at the 1.4 μm photosphere. The third row shows the ratio of the photospheric pressures at 1.4 and 1.25 μm, a proxy for the amplitude of the water feature in the WFC3 bandpass. The last five rows show the abundances of important molecules slightly above the 1.4 μm photosphere, defined where the contribution function reaches three quarters of its maximum value.