Traders see Seoul's July 12 overnight low clustered around the 23–25 °C range because the ongoing Changma monsoon continues to deliver extensive cloud cover and scattered showers that limit nighttime radiative cooling. Recent model guidance shows modest differences in the timing and extent of cloud breaks or rainfall intensity over the next 48 hours, which directly influence how far temperatures can fall below the seasonal 24 °C climatological average before sunrise. Persistent high humidity and light winds further suppress cooling, keeping outcomes below 22 °C or above 26 °C less probable unless a clearer, drier slot develops. Updated KMA and global ensemble runs expected in the next day will likely sharpen the distribution ahead of market resolution.