Beautiful day across Japan and Korea today as temperatures climb in to the high 20s. (Low 80s) Downside, this is going to help fire up a storm on Tuesday and Wednesday that will roll its way across the area bringing winds up to 100kph, 150mm of rainfall in Kyushu and strong thunderstorms especially in western Japan。
As this area of low pressure seen on Satellite Images (Below) tracks out of China it will rapidly deepen dropping its pressure from 1004hpa to 975hpa in 36hrs. This is impressive even for spring low standards.
Winds will be highest along the Korean Coast Tuesday night and much of Western Japan through Wednesday morning. The highest gust according to JMA will be up to 108kph along western coastal areas. Enough to cause damage to light structures.
Okinawa will also getting some gust over 30MPH. Along with passing thunderstorms through Tuesday afternoon and evening.
Central Japan will still see a wind threat but it will not be as intense as further West. The coastal Pacific of Honshu could get Tropical storm strength winds from the South along with high surf up to 3-4 meters high. No one should be out at the beach though since the sun will be gone and most will be seeing heavy rainfall. Over 150mm of precipitation is possible in Kyushu and Western and Central Honshu. If we see any training from storms lining up a long the front as it passes by we could get much more than that number ushering in the threat of flooding and landslides.
Good news is that the storm is moving from the South west to North east, meaning it will bring in warmer spring / summer air with it across Eastern China, Korea and Japan. So after a short cool down temperatures will rise quickly back up for a stretch to wrap up the work week.