Sea warmer than usual as summer heats up

ENTICING: Bream Bay swimmers were yesterday finding this year's water temperature warmer than at the same time last year. PHOTO/RON BURGIN

More hot summer weather is on the way for Northland, but the sea may offer little relief, the water temperature almost 1C higher than normal.

The temperature in Northland officially hit 30C on January 4 and 5, according to the MetService.

But with the official temperature for Whangarei taken inside a louvred box at Whangarei Airport the real temperature is likely to have been higher than that.

Niwa weather experts have just released a climate forecast to the end of March that says there is a good chance Northland's daily high temperatures will be above normal.

Niwa environmental scientist Darren-Ngaru King said Northland was in a good position for more great summer weather with a 50 per cent chance temperatures would be above average and a 30 per cent chance they would be near average. There was also a 20 per cent chance they would be colder than normal.

Mr King said the average daily highs for Whangarei were 23.4C for January; 24.5 in February and 23C for March. For Kaitaia, the January average high was 23C; 24.3C for February and 22.9C for March.

Kaikohe had a January average high of 23C; 23.5C in February and 21.9C in March while Dargaville's average daily high was 23.4C in January; 23.8C in February and 22.3C in March.

"But probably more interesting ... is that the monthly sea surface temperature (SST) anomaly for New Zealand was approximately +0.9C in December.

"This is now the 12th consecutive month that SSTs have been warmer than normal around New Zealand, and is the highest monthly anomaly for the 2013 year. The large region of warmer-than-normal water to the east and southeast of New Zealand, which has been an unusually persistent feature of the SST field for much of 2013, has expanded to engulf New Zealand.

"Also, the warmer-than-normal SSTs have re-intensified northeast of New Zealand, between the North Island and Fiji. Sea surface temperatures are expected to remain above average overall for the coming three months around New Zealand."

Mr King added, "That 0.9C above average SST is the warmest in the 10 years I've been looking at these things. And the thing about SSTs is that they then really drive up air temperatures and they are really significant for you."