A storm system currently bringing rain to eastern China and Taiwan will strengthen as it tracks northeast in the coming days.
The strengthening of the storm system will continue as it tracks just east of Japan Saturday and Sunday.
The heaviest rainfall will reach Kyushu and Shikoku on Friday then spread through southeastern Honshu on Friday night where precipitation will mix with snow.
On Saturday, heavy rain will fall across the lower elevations of southern Honshu and Shikoku while heavy snow falls in the higher elevations.
Around Tokyo, a burst of snow is possible late Friday night into Saturday morning before mixing with and changing to rain during the day.
A slushy inch or two is possible in the city with higher amounts to the north and west.
Following the snow, heavy rainfall will total 25-50 mm (1-2 inches) around Tokyo which could lead to some flooding problems.
The greatest threat for flooding will occur from near and south of Osaka northeastward through Tokyo.
While snow is expected to change to rain in locations such as Tokyo and Sendai, heavy snow will total several feet in the Japanese Alps.
The main impacts from the storm will shift into northeast Honshu by Sunday then lift into Hokkaido Sunday night and Monday.