Unusually warm weather in parts of Japan has resulted in an earlier start of the pollen season.
Private weather forecaster Weather News says cedar pollen became prevalent in Tokyo last week. It says the high season for cedar pollen in the area arrived 10 days earlier than average.
The forecaster says cedar pollen was prevalent last Wednesday in southern parts of Kanto as well as in Shizuoka Prefecture on the Pacific coast.
The company said it expects the peak of pollen dispersion will likely continue until the end of March.
However, it says the amount of pollen in the air nationwide will likely be about 85 percent of the average. It says last year's long rainy season and bad weather in summer slowed the growth of cedar's male flowers.