Recent National Weather Service model runs point to a modest warming trend across coastal Southern California through mid-week, with ensemble guidance favoring daytime highs near 74–77°F at Los Angeles International Airport on May 19. Persistent but weakening onshore flow and a variable marine layer remain the dominant controls, limiting full solar heating while sea-surface temperatures hover near seasonal norms. Traders weigh the narrow spread between the 74°F-or-higher and 72–73°F bins because small shifts in boundary-layer mixing or afternoon wind direction could push the official high across the 74°F threshold. Historical May climatology shows a 2–3°F day-to-day variability at this time of year, underscoring why the market prices these two outcomes so closely together ahead of the next updated forecast cycle.