Kona lows are storm systems that set up to the west or northwest of the islands and draw up lots of moisture from the south, creating messy and sometimes dangerous conditions. They can bring widespread heavy rain to the islands with the threat of flash flooding, as well as damaging, gusty winds.

Flash flood warnings remain in effect across multiple islands late Friday night as heavy rainfall continues to cause flooding and road closures. On Oahu, heavy rainfall is beginning to ease, but flooding problems are still being reported across the island.

An updated flood advisory was released by the National Weather Service on Wednesday at 10:55 p.m. in effect until Saturday at 8 a.m. for Allegheny County.

On Monday at 11:45 a.m. a flood warning was issued by the National Weather Service valid from Tuesday 8 a.m. until Wednesday 8 a.m. for Middlesex County.

Trees were partly submerged by water after the Grand River flooded parts of the Grand Rapids area in Michigan, footage filmed on Sunday, March 15, shows.Nathan Voytovick of Nate’s Dronography told

On Saturday at 4:50 a.m. an updated flood watch was released by the National Weather Service in effect until 5 p.m. for Clatsop County Coast, Tillamook County Coast, North Oregon Coast Range Lowlands,