Ongoing heatwave conditions across South Korea, fueled by a strong North Pacific high and suppressed monsoon activity, underpin trader focus on 37–39°C outcomes for Busan’s July 29 maximum. Coastal location introduces key variables: sea breezes from the Korea Strait can cap afternoon peaks through advection of cooler marine air, while reduced cloud cover under the ridge would allow greater solar insolation and push readings toward 39°C. Model spreads in boundary-layer moisture and exact steering flow create the tight 32–23% split between 38°C and 39°C, with KMA short-range guidance and ensemble runs due in the next 24–48 hours likely to refine whether daytime heating exceeds recent 34–35°C observed highs. Historical July extremes near 35°C provide context, yet this season’s elevated baseline raises the odds of an outlier peak.