While Japan is recovering from former Typhoon Phanfone, Super Typhoon Vongfong will turn northward across the Western Pacific Ocean and bring a new threat by the end of the week.
Vongfong brought flooding rainfall and damaging wind to the northern Mariana Islands on Sunday, local time. Wind gusts over 89 kph (55 mph) and rainfall over 75 millimeters (3 inches) were common.
It is now equivalent to a Category 5 hurricane with sustained winds of 270 kph (166 mph).
"Vongfong is the strongest tropical cyclone we've had all year anywhere on Earth," AccuWeather.com Meteorologist Jim Andrews said.
The strength of Vongfong has surpassed that of Super Typhoon Genevieve which, at its most powerful, had sustained winds of 257 kph (160 mph) in the West Pacific.
The combination of light wind shear and warm water allowed Vongfong to rapidly strengthen across the western Pacific Ocean so far this week.
Late in the week, while Vongfong is located south of Japan, the typhoon is expected to slow down and make a turn to the north. While there remains some uncertainty in the exact track of the storm, confidence is high that the powerful cyclone will track north toward Japan with the potential for a landfall in mainland Japan by early next week.
"Destructive winds and flooding rain will be the top threats," Andrews said.
The first target will be the northern Ryukyu Islands which could begin to feel impacts from Vongfong as early as Saturday or Saturday night.
"It's not out of the question that the storm gets hooked westward, making direct landfall on one or more of the northern or central Ryukyu islands late Saturday into Sunday, local time," Andrews said. "That would mean typhoon-force winds and flooding rain."
This animated GIF shows Vongfong tracking across the western Pacific Ocean. (NOAA/Satellite)
The worst impacts across mainland Japan are expected from Monday into Tuesday, with typhoon-force winds and inundating rainfall expected.
"How far west Vongfong is able to run will also determine whether there is a direct landfall in the island of Kyushu and thus the exact impact in cities such as Kagoshima," Andrews said.
Many areas at risk from Vongfong are still recovering from more than 150 millimeters (6 inches) of rain and strong winds that hammered eastern Japan from Sunday into Monday as Typhoon Phanfone moved through the region.
Tokyo was deluged by 272 millimeters (10.71 inches) of rain ahead of and during the height of Phanfone.
"Phanfone was a huge rainstorm for Tokyo, one of the biggest I can remember," Andrews added, noting moisture from the storm interacted with stalled front, prolonging the duration of rain.
There could be several inches of rain in Tokyo, almost exactly one week after Phanfone's impact.
"The threats are the same as they were with Phanfone," Andrews said. "There are some likenesses but also some differences in Phanfone's track. The results can vary markedly with small differences in track and storm speed."
All interests in Japan should continue to monitor this powerful typhoon.