Northland motorists are being warned to take care on the roads today, with heavy rain and thunderstorms forecast and the possibility of tornadoes.

Metservice has issued a severe thunderstorm watch for the region.

From this afternoon into the early hours of Monday morning, thunderstorms could cause heavy rain of between 15 and 25 millimetres an hour and winds could reach 100 kilometres per hour.

Surface and flash flooding and slips are likely and driving conditions could be hazardous with very poor visibility.

Possible localised tornadoes could also damage trees and powerless.

Civil Defence has advised people to relocate items from any areas that are prone to flooding.