**Forecast models indicate Istanbul's overnight low on August 30, 2026, will likely settle between 19–22°C, aligning closely with the tightly bunched market prices (19–22°C outcomes holding ~79% combined implied probability).** Official guidance from sources including the Turkish State Meteorological Service (MGM), Met Office, and multiple numerical models shows a mostly sunny or partly cloudy day with highs near 27–29°C, followed by calm-to-light northerly winds and clear to partly clear skies overnight. These conditions promote moderate radiative cooling after sunset, with dew points around 18–20°C limiting further drops. Historical August climatology for Istanbul places typical minima near 20°C, and recent observations confirm temperatures running slightly below seasonal norms amid variable cloud and northerly flow. The narrow spread among leading outcomes reflects genuine forecast uncertainty rather than model disagreement. Key differentiating factors include exact wind speeds (calmer conditions allow deeper cooling toward 19°C or below), residual cloud cover or humidity (which traps heat and favors 21–22°C), and urban heat-island effects that can raise recorded lows by 1–2°C in central districts versus suburban stations. With resolution likely hinging on the precise minimum observed between midnight and dawn, traders are pricing the balance of these variables near even odds across the 19–22°C band.