Tokyo Electric Power Co. is rushing to install a cover over a building at its crippled Fukushima Dai-Ichi nuclear plant to shield it from wind and rain as Typhoon Ma-on approaches Japan’s coast from the south.

Work on the cover for the turbine building of the No. 3 reactor started Monday morning, Junichi Matsumoto, a general manager at the utility known as Tepco, said at a briefing in Tokyo. The transfer of tainted water for storage in a barge docked next to the plant was halted, spokesman Satoshi Watanabe said by telephone.

The eye of Ma-on, which is categorized as “strong” by the Japan Meteorological Agency, was about 640 miles southwest of Tokyo  early Tuesday morning in Japan, according to the U.S. Navy Joint Typhoon Warning Center.

The storm was moving north at 16 mph with winds blowing at 86 mph, the Navy reported. Ma-on is forecast to continue heading north and may cross the coast of the southwestern island of Kyushu this morning and pass off Tokyo tomorrow. An earlier forecast track indicated the storm may pass over the Fukushima plant by July 21.

The Japanese weather agency issued warnings for floods and high waves along the southern coast from Okinawa to Tokyo.

Last year, the eyes of two storms passed within 300 kilometers of Tohoku, as the area where the plants are located is known, data from the weather agency show.

Tepco is on schedule to contain radioactive emissions from its Fukushima Dai-Ichi plant, which suffered three reactor meltdowns after the March 11 earthquake and tsunami, Prime Minister Naoto Kan said on July 16 during a visit to the area. Tepco was expected to announce Tuesday that it has completed the first phase of its plan to resolve the crisis, he said. Tepco has achieved its phase one goal of keeping the reactors cool and reducing the amount of radiation being emitted by mid-July, Kan said while visiting a sports center near the Fukushima plant where workers rest.

Much of the work has been focused on decontaminating highly radiated water that flooded basements and trenches around the damaged reactors as Tepco doused the units to keep them cool.

Water overflowed from damaged reactors, impeding efforts to bring the situation under control. A decontamination unit started work last month, though its operation has been intermittently halted due to leaks and other malfunctions.

Tepco’s so-called road map for resolving the crisis was released on April 17 and envisages bringing the plant to a safe status within nine months. The second phase involves bringing the reactors to a state known as cold shutdown, where the fuel’s temperature is held below 212 degrees Fahrenheit.

Mandatory power savings have been imposed in some areas of Japan after the earthquake and tsunami knocked out capacity and caused the reactor meltdowns at Fukushima. Other reactors closed down safely after the disaster or have been idled for scheduled maintenance, exacerbating shortages.

Japan’s weather agency, meanwhile, issued warnings for floods and high waves for parts of the country’s southern coastline as Typhoon Ma-on headed north toward the island of Kyushu.  Warnings extended from the Okinawa to Kyushu and other areas along the coast as far as Tokyo, the agency.

All Nippon Airways Co. canceled afternoon flights to and from the Miyazaki in Kyushu, the company said on its website. Flights to and from Kagoshima may also be delayed or diverted, the airline said.

Japan Airlines Corp. canceled 24 flights affecting about 2,150 passengers by 11:30 a.m., the company said in a faxed statement.

Ma-on was moving north and may make landfall on Kyushu by 12 p.m. local time Tuesday, the Japanese weather agency said.

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The Associated Press contributed to this report,