**Recent forecast updates for Istanbul show a frontal system approaching on September 14, introducing notable uncertainty in overnight minimum temperatures.** Model runs from sources like ECMWF and GFS indicate daytime highs near 23–24°C with scattered showers possible, while overnight lows are projected between roughly 15–19°C depending on cloud cover, wind direction from the north-northwest, and precipitation timing. This spread creates balanced market-implied odds, with 14°C or below and 24°C or higher both near 42% as traders weigh the potential for stronger cooling versus milder conditions under partial clearing. Historical September climatology for the region features typical minima around 17–18°C, but current steering patterns and moisture could shift the outcome either way before resolution. Updated model guidance and local observations over the next 48 hours will likely refine these probabilities.