Long-range forecasts which predicted rain for much of rugby-test week in Napier and Saturday night's game seemed to be on the button last night - with more of the wet stuff expected in one one of the region's wettest first weeks of September in years.

The 51.8mm whole-of-month September average at the Hawke's Bay Airport weather station had been exceeded in the first three days of the month.

And MetService duty forecaster Mariken van Laanen said in Wellington more "periods of rain" are expected today and tomorrow.

There "may be some heavy falls," she said, indicating the southeasterly weather will bring out the plastic poncho raincoats for many of the 22,750 fans expected for the Rugby Championship match between the All Blacks and Argentina at McLean Park tomorrow, starting at 7.35pm.


The forecasts, which include a maximum temperature for Napier of 15C tomorrow cooling to an overnight minimum of 8C, provoked memories of the 2011 Rugby World Cup match at McLean Park between France and Canada. That was a mid-September game also hit by rain.

Better news was the rain was expected to ease to showers on Sunday and Monday, with what Ms van Laanen said was expected to be "quite nice" weather over the following days, leading to Hawke's Bay's first Ranfurly Shield defence against Otago at McLean Park on September 14.

Despite the sudden rain at the start of the month, predictions for Hawke's Bay over the Spring months are normal to marginally more rain than than average, according to Niwa's outlook released yesterday.

Statistics for August in the region were unspectacular, although Dannevirke and Waipawa each recorded their second-highest August maximum - 20.7C and 21.7C respectively on August 2.

The weather was causing few disruptions at McLean Park, where ground preparation was continuing with pitch signage being carried out yesterday.