Powerful Hurricane Lane weakened slightly as it swirled toward Hawaii on Wednesday. U.S. forecasters warned that its heavy rains and life-threatening winds still posed a major threat.

Reuters reports, the U.S. Central Pacific Hurricane Center downgraded Hurricane Lane to a Category 4.

The storm threatened to dump as much as 20 inches of rain over parts of the islands.

Hawaii is already coping with the three-month eruption of Kilauea volcano.