Trader consensus on Polymarket reflects tight uncertainty in National Weather Service guidance and model ensembles for downtown Los Angeles highs on April 19, with GFS and ECMWF runs clustering around 71-73°F amid moderate onshore flow (10-15 kt) fostering a persistent marine layer of low stratus clouds. This coastal stratus deck, common in April climatology (average high 73°F), typically burns off by midday but could cap peaks at 70-71°F if advection strengthens, while earlier clearing or subsidence warming under a building high-pressure ridge offshore favors 72-73°F or 74°F+. Recent 24-hour trends show seasonable 70s with no major shifts, though overnight model updates may refine cloud burn-off timing and wind shear differentials. Resolution hinges on official USC observations.