Sweltering days ahead
The golden weather is set to continue in Marlborough with 30 degree Celsius temperatures forecast for at least a few more days.
MetService meteorologist Dan Corbett said it was 28.4C in Blenheim at 3pm yesterday, while Kaikoura was a comparatively chilly 19.6C. Twizel, Roxburgh, and Omakau topped the temperature charts with 31.6C, while Nelson and Christchurch both hit 23C.
Climate scientist Jim Salinger had predicted that parts of the South Island's east coast between Timaru and Marlborough could top 40C yesterday. Dr Salinger said the high temperatures were being buoyed by a gentle northwesterly and warm air clashing with the tailend of tropical cyclone Oswald.
It mirrored conditions that created a 40C-plus day in Canterbury on February 7, 1973, when the temperature in Rangiora hit a New Zealand record of 42.4C.
Mr Corbett said there was a high pressure system southeast of New Zealand which was bringing warm temperatures to many parts of the country. He expected Marlborough to peak in the low 30Cs.
For the temperature to break through to 40C it would require days of strong northwest winds. The wind was predominantly coming from the northeast, he said.
"Over the next 24 to 48 hours we will see the hints of a northwesterly but we will be not be seeing that strong warm dry northwesterly.
"That is how you got 42C in Rangiora."
He said the terrain in Blenheim was shaped like a bowl, trapping heat and keeping temperatures up.
There could be considerable variance in temperature readings in the area. "But we combine the readings from a number of stations to make an average reading for the region."
More cloud and moisture was expected to arrive at the end of the weekend with a shower system moving in on Monday, he said.
Climatologist Dr Andrew Tait of Niwa (National Institute of Water & Atmospheric Research) said Blenheim's warmest temperature on record was 37.8C, the same day, February 7 1973, that Rangiora hit 42.4C. Kaikoura's warmest ever day was in February 2011 when it peaked at 34.3C.
Dr Tait said it was reasonably rare for a high pressure system to sit over the country for as long as it had and very rare for New Zealand to get temperatures higher than 40C.
Symptoms of dehydration and heatstroke include:
How to avoid it:
People susceptible to the heat include:
Information from Springlands Health GP Grant Johnston
The Marlborough Express