Recent National Weather Service model runs and ensemble guidance point to a building southerly flow ahead of a high-pressure ridge, supporting afternoon highs near 86–88 °F at the official LaGuardia station on May 17. Boundary-layer mixing and limited afternoon cloud cover favor the upper end of that range, while any earlier sea-breeze or convective development could cap temperatures a degree or two lower. The tight spread between the 86–87 °F and 88–89 °F buckets reflects modest model disagreement on peak heating timing and wind speeds, with historical May climatology placing typical highs around 70 °F. Traders are therefore weighting the latest guidance most heavily, leaving room for the final observed maximum to shift within the 84–91 °F window as new model runs arrive overnight.