Summer drought risk blows in

Drying northwesterly winds that swept Wairarapa during Christmas-New Year, followed by searing heat, have confirmed the district is at risk of a summer drought.

The latest Niwa seasonal outlook for January/March confirms late summer rainfall, soil moisture levels and river flows are likely to be "below normal or near normal."

Rain gauges, monitored by private landowners in parts of Wairarapa, show that not only has 2013 started out dry and hot but that December was well down in some areas on rainfall stats in what was generally a dry year.

At Ponatahi, rain fell on 11 days of the month but on three of those occasions the amount recorded was less than a millimetre, hardly enough to register.

The heaviest fall was on Boxing Day, when 21.3mm were recorded but by the month's end only 61.2mm had fallen, exactly half the amount that fell in December the year previous.

The year ended with a total recorded rainfall at Ponatahi of 928.4mm, down from 1036.5mm in 2011.

Even in what is generally regarded as the green belt, along the foothills of the Tararua Range, in North Wairarapa, Hastwell and Mauriceville rainfall has been patchy and soil moistures levels down.

A wet winter was followed by a dry, squally spring that brought little benefit to farmers because northwesterlies frequently followed to quickly destroy any good rain may have brought.

In recent days, temperatures throughout Wairarapa soared to about 30 C but the latest forecasts predict the return of strong, drying northwesterlies.

Ten years ago scientists advising the Government's Climate Change Project predicted wairarapa would get up to 3 C hotter during the following 100 years.

That would be part of a pattern that nationwide would see extreme, hot days, heat waves and fewer winter frosts.

Varied rainfall, the scientists said, could result in more intense, heavy rain storms that would make flooding up to four times more frequent by the year 2070.