According to the Bloomberg article (7/7/2014), the US Navy's Joint Typhoon Warning Center in Pearl Harbor, Hawaii, says it may become a Cat-5 equivalent by Tuesday though others disagree:
High winds, crashing waves and a dangerous storm surge are threatening Okinawa, including its capital Naha, as Super Typhoon Neoguri nears Japan.
Neoguri carried maximum sustained winds of about 150 miles (241 kilometers) per hour, making it the equivalent of a Category 4 hurricane on the five-step Saffir-Simpson scale used in the U.S., according to the Navy’s Joint Typhoon Warning Center at Pearl Harbor, Hawaii. It was about 283 miles south-southwest of Okinawa.
Japan has issued emergency warnings for Okinawa calling for high waves, gale-force winds, strong storm surge and thunderstorms. Heavy rain warnings are in effect for portions of Kyushu, Japan’s southernmost main island, and for southwestern portions of Honshu, Japan’s main island. There are two idled nuclear plants on Kyushu.
The storm was moving north at 12 mph, according to the Japanese Meteorological Agency. The U.S. Navy predicts the storm may reach 160 mph by tomorrow, however Jeff Masters, a founder of Weather Underground in Ann Arbor, Michigan, thinks it may have peaked in intensity.
“The official Joint Typhoon Warning Center forecast calls for Neoguri to complete its eyewall replacement cycle and intensify into a Category 5 typhoon with 160 mph winds by Tuesday,” Masters said in an e-mail. “While this is certainly possible, I think it is more likely that Neoguri has peaked in intensity, given the level of disruption to the storm apparent on satellite images.”
(Full article at the link)
Image from NOAA:
The US military has reasons to worry, as Okinawa is home to numerous US military bases, as you can see in the map below (by Regional Security Policy Division, Executive Office of the Governor Okinawa Prefecture):
Typhoon 8's potential path, from the US Navy Joint Typhoon Warning Center:
Kyushu Island has two nuclear power plants, Genkai Nuclear Power Plant in Saga Prefecture in the north and Sendai Nuclear Power Plant in Kagoshima Prefecture in the south. Sendai Nuclear Power plant is facing the South China Sea (i.e. facing the coming typhoon). If the prediction by the Joint Typhoon Warning Center is correct, the typhoon will make a landfall in between, in Kumamoto Prefecture.
Sendai Nuclear Power Plant is all set to be given the approval from Japan's Nuclear Regulation Authority that it has cleared the examination under the new nuclear regulatory standards and is ready for the restart, as soon as the local municipalities approve the restart (which is a given).