January wetter, cooler: Niwa

Holiday makers rolling up wet tents and long lines to get into the movies and to the swimming pool have been frequent sights in Otago this summer as people escape the rain.

So it will come as no surprise to Otago residents and visitors that Niwa figures show January to date has been wetter and cooler than normal.

With 11 days of the month still to go, Queenstown, Balclutha and Wanaka have all had more than their normal rainfall for January, 150%, 131% and 124% respectively.

For first 20 days of the month, it rained on 14 days in Balclutha, 10 in Dunedin, 11 in Queenstown and eight in Wanaka.

Temperatures so far were below January's average in Alexandra by 1.5degC, Wanaka 1.2degC, Queenstown 1degC and 0.9degC in Oamaru.

However, Dunedin's temperature so far was near its average at 15.3degC.

Raineffects hydrologist Dave Stewart said the cooler and wetter than average weather for January was the result of a series of systems preceded by a very strong, moist northwesterly.

That was followed by a high pressure ridge with a cold southerly in behind it.

''We've been in this regime since just after Christmas but it shows signs of waning.''

It was six to eight days since the last heavy rainfall in the headwaters, which was giving the lakes time to drop from their near flood levels, he said.

These sorts of systems usually lasted from three to eight weeks so it was possible this one was on its way out, although ''it could come back''.

There was a front expected to bring rain to the South tomorrow, but it had weakened and was not expected to be anything like those that dropped 100mm-plus of rain in to the Southern Lakes, he said.


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