Japan's Diet has revised legislation so that weather companies and other private businesses that pass screening can forecast floods and mudslides.

The Lower House plenary session unanimously passed revisions to the Meteorological Service Act and the Flood Prevention Act on Tuesday.

Previously, research institutions and private firms in Japan had not been allowed to forecast natural disasters due to difficulties in making accurate predictions.

But there has been growing demand for detailed information corresponding to local needs, following a series of disasters triggered by heavy rains.

The Meteorological Agency and others say weather companies can now make highly precise forecasts using advanced simulation techniques.

The central government also now provides its flood prediction data to prefectural governments, so that private firms will be able to issue notices on long-term risks and localized disaster-control information.

But after the legal revisions, private-sector forecasts will be sent only to administrative offices and businesses, to prevent confusion with the current government-issued forecasts.

The revisions are expected to help limit damage to public transport facilities and private-sector plants, and speed up preparation of shelters and evacuation methods in areas at high risk of floods.