Latest National Weather Service and Global Forecast System model runs point to a daytime high in the upper 70s to low 80s for New York City on May 18, supported by southerly flow advecting mild air and partly cloudy skies that permit moderate solar heating without triggering strong convective instability. This narrow forecast range explains the closely matched market-implied odds across the 80–81°F, 82–83°F, and 84–85°F bins, where small differences in cloud thickness, wind direction shifts, or afternoon mixing depth can alter peak readings by a few degrees. Historical mid-May Central Park normals near 72°F provide context for the current above-average signal, while upcoming model updates tonight will refine resolution criteria tied to official observations.