**Short-term forecast consensus for Busan on September 18 centers on a daily high near 24–26°C, shaped by moderate northeasterly flow, increasing cloud cover, and a modest chance of light rain or drizzle.** Official and model guidance from sources including globalmeteo, WindBorne, and yr.no indicate highs of roughly 24–25°C (75–77°F) under mostly cloudy to overcast skies, with lows near 22–23°C. Northeast winds of 10–16 mph (roughly 5–8 m/s) advect cooler, humid maritime air from the Sea of Japan, limiting daytime warming while keeping humidity elevated (60–75%). A 20–65% probability of light precipitation, often tied to weak frontal or orographic lift, further caps peak temperatures by reducing solar insolation. This setup aligns with the climatological September average high near 25–26°C for Busan, though the current pattern shows slightly more cloudiness than clear-sky analogs. Model spread remains modest two days out, primarily from differences in exact cloud thickness and timing of any showers rather than large-scale synoptic shifts. Traders therefore assign roughly equal implied probabilities across the 22–29°C band, reflecting the narrow envelope of likely outcomes and the low likelihood of extremes given the stable steering flow and absence of strong warm advection. Updated model runs and official briefings from the Korea Meteorological Administration will provide the next refinements before resolution.