Japanese weather officials say a severe tropical storm is forecast to approach eastern and northern Japan and could make landfall sometime between Monday and Tuesday.

The Japan Meteorological Agency says Severe Tropical Storm Nari is traveling north at 35 kilometers per hour as of 10 a.m. over waters 170 kilometers south-southeast of Choshi City in Chiba Prefecture.

It has a central atmospheric pressure of 985 hectopascals and is packing winds of up to 90 kilometers per hour near its center, with gusts of up to 126 kilometers per hour. Strong winds of over 54 kilometers per hour are blowing within 440 kilometers on its eastern side and 220 kilometers on its western side.

The officials say waves are high in the Ogasawara Islands, located south of central Tokyo.

They say the severe tropical storm is expected to move north as it develops and likely pass east of the Kanto region by Monday night before moving off the coast of Sanriku.

The officials say it will then travel to the Hokkaido region, in northern Japan on Tuesday and turn into an extratropical low pressure system.

The weather officials warn that, on Tuesday, the severe tropical storm will approach the Pacific side of eastern and northern Japan and is expected to make landfall.

They say they expect strong winds to blow in northern Japan.

On Monday, winds of up to 90 kilometers per hour are expected in the Tohoku and Kanto regions, and 64.8 kilometers per hour in the Izu Islands, with maximum gusts reaching an hourly speed of 126 kilometers in the Tohoku and Kanto, and 90 kilometers in the Izu Islands.

Meanwhile, the meteorological agency says rainclouds have been developing mainly over western Japan, due partly to the impact of a tropical depression near Kyushu.

The agency warns that bands of heavy rain clouds are expected to form especially in the Tokai region from Monday night through Tuesday before noon. It says the danger of water-triggered disasters could rapidly increase, and is urging caution for flooding in low-lying areas and landslides.

The agency says warm and moist air is flowing into the tropical depression west of Kyushu and a low pressure system over the Tsushima Strait, and rainclouds are forming in the Kyushu and Shikoku regions.

In the hour through 8 a.m. on Monday, extremely heavy rain of 52 millimeters fell in the town of Ino in Kochi Prefecture, and 32 millimeters in Tamana City in Kumamoto Prefecture.

The agency says the tropical depression is expected to gradually weaken, and the low pressure system is forecast to travel north over the Sea of Japan.

It says that atmospheric conditions are expected to become extremely unstable by Wednesday in western and eastern Japan. It says extremely heavy rain is expected with localized downpours including thunder and lightning.

The amount of rain expected in the 24 hours through Tuesday morning is up to 200 millimeters in the Tokai and Shikoku regions, 180 millimeters in the Kinki region, 80 millimeters in the Chugoku and southern Kyushu regions.

In the 24 hours through Wednesday morning, up to 150 millimeters are forecast in the Tokai region. In the following 24 hours through Thursday morning, 200 millimeters are likely in the Tokai region.

The agency is urging caution for landslides, flooding in low-lying areas and swollen rivers. It also calls on people to be on the alert for lightning and gusts, including tornado, and hails.

The agency warns that the weather situation could deteriorate during the night.