[1] Early on 20 October, the Japan Meteorological Agency (JMA) upgraded an area of low pressure into a tropical depression.

The remnants of Chaba continued to weaken as it moved northeast, but strengthened again in approaching the Gulf of Alaska into a major storm[15] with 55-knot winds,[16] kicking up 40–50-foot waves, with pressure as low as 939 mb.

[17] The storm's center came ashore in the vicinity of Cordova, Alaska on 1 November, but not before pulling an atmospheric river of moisture into the American Pacific Northwest, setting a record[18] for that date of precipitation in Seattle.

[19] Islanders in southern Japan started sandbagging doors and reinforcing windows as Chaba churned closer.

[20] Strong winds and heavy rains lashed through Okinawa and there were a lot of concerns about the island of Amami which was in the typhoon's path.

[23] On Minami-Daito Island in Okinawa Prefecture, winds from the typhoon gusted up to 160 km/h (99 mph), resulting in roughly 500 residences losing power.