A spate of crashes on Hawke's Bay roads has brought a warning for drivers to drive to the conditions in the changeable weather between seasons.

It was not clear how much or even if damper conditions had been a factor in the incidents - one serious crash and three minor - but Eastern Police road policing prevention manager Dan Foley said: "The same lines apply — drive to the conditions at the time."

The crashes happened within about five hours, the most serious on the Napier-Taupo highway being followed by incidents from which no injuries were reported in Willowpark Rd, Hastings, a short while before midday, State Highway 50 near Tikokino about an hour later, and Korokipo Rd, Waiohiki, soon after 1.30pm.

Conditions throughout the area from Central Hawke's Bay to Wairoa were cloudy throughout the day after mainly light rain, generally no more than about 7mm.


Temperatures were expected to drop slightly from Wednesday's highs of about 18 degrees, and more rain was forecast over the next two days to the weekend, possibly heavy in some places.

While MetService late Wednesday had no weather warnings in place for Hawke's Bay, heavier rain was expected further north. The national agency said up to 100mm could be expected to have fallen in East Coast areas north of Gisborne in the 21 hours to 6am Thursday, with peak rates of 10-20mm an hour.

The seasonal expectation is consistent with the experience around September 5 last year, when heavy rain causing flooding in some parts of Hawke's Bay.