The JTWC reported that Choi-wan is located 593 km east-southeast of Iwo To and has been moving north-northwest at a speed of 7 km/h (4 knots) over the past six hours. Choi-wan is expected to move generally northward.
Its forward speed will increase significantly starting on the second day, as Choi-wan is caught up in a mid-latitude low-pressure trough and interacts with strong upper-level airflow.
Extratropical transition (ETT) is forecast to begin in 60 hours and conclude within approximately three days.
In terms of intensity, Choi-wan is expected to begin weakening gradually at a steady rate—dropping by 20 km/h (10 knots) every 12 hours—over the next 60 hours.
This weakening trend could accelerate depending on the timing and severity of an eyewall replacement cycle.
If the outer eyewall completely chokes off the inner eyewall, the rate of weakening could increase.
After 12 hours, ocean heat content will begin to decline, further supporting this weakening trend.
