Heavy rain and easterly gales has prompted warnings in the Western Bay of Plenty.

Police are advising motorists to drive with caution, especially over the Kaimais.

MetService media and communications meteorologist Dan Corbett says people need to keep an eye on the weather as things could worsen.

Periods of heavy rain are expected until tomorrow morning with the heaviest rain prediction for this morning, says the MetService.

The MetService has also issued a warning for eastern Northland and the Coromandel Range.

In addition, this watch is for the possibility that easterly gales could become severe about exposed parts of Northland, Auckland and Waikato, near the Kaimai Range.

The strongest winds in Northland are expected from Thursday evening through to Friday morning, in Auckland from Friday morning through to Friday night and in eastern Waikato from Friday morning through until early Saturday morning.

Media and communications meteorologist Dan Corbett says the weather system originated in the tropics.

'The band of persistent rain associated with this low will gradually spread down to central New Zealand by the end of the weekend.

'Rugby fans heading to the big match in Hamilton on Saturday night might want to grab a rain coast just in case, but the main rain band should have passed over by game time.”

Dan says by next Monday, the winds are expected to have swung from easterlies to westerlies, bringing cooler conditions.