Severe Tropical Storm Chanthu (2016)

On August 11, the JMA began tracking a tropical depressionwhereas the JTWC issued a Tropical Cyclone Formation Alert, as it was located about 695 km (432 mi) west-northwest of Guam. After meandering eastwards, the JTWC designated the system as 09W, while the JMA immediately upgraded 09W to a tropical storm and assigned it the name Chanthu on August 13.The JTWC followed suit early on August 14, With an improving LLCC, Chanthu rapidly developed into a severe tropical storm from the JMA, as it was later located over in an area of favorable environments of strengthening. Despite a high chance of strengthening and a well-defined LLCC, Chanthu stopped generating convection as the JMA downgraded it to a tropical storm.

Later that day, flaring convection was associated with its LLCC as it was beginning its extratropical transition while interacting with mid-latitude flow. Therefore, early on August 17, Chanthu restrengthened into a severe tropical storm strength as it attained its peak intensity with a minimal pressure of 980 millibars (28.94 inHg), while east of the Japanese archipelago of Honshu. Shortly thereafter, the JTWC issued its final warning on Chanthu. The JMA issued its final warning a few hours later as it made landfall over Cape Erimo of Hokkaido, Japan, at peak intensity. Its extratropical remnants were traceable for a few more days before being last noted over the Russian Far East on August 20