February 1973: Pressures were unusually high over New Zealand, and this was one of the driest months on record, besides being sunny and warm with some exceptionally high temperatures. January had also been dry, and the greater part of the country made little pasture growth. Drought conditions became fairly general.

Rainfall: For the country as a whole rainfall was only 25% of the normal value. Negligible amounts of less than 10% of the normal were recorded over about half the North Island, mainly in western districts; also in many inland districts of the South Island, in Nelson and in Marlborough, and in coastal North Otago. [Stratford Mountain House had 4mm, barely 1% of average]. In the North Island this month was not as dry as January 1908. The only areas with rainfall about normal were Fiordland, with Stewart Island and parts of South Westland, where nearly all the rain fell in the first 10 days; and also some of Gisborne and northern Hawkes Bay. Sites with nil rainfall included Manaia, Motueka (Riwaka), Appleby and Blenheim Aero. Milford Sound reached its average with 595mm, nearly all of it falling in the first week.

Temperatures: Temperatures were mainly above normal by up to 3C, with highest departures over inland South Island districts and the Canterbury Plains. It was very warm east of the ranges from the 4th to the 7th. Until this time the record high temperature for New Zealand was 38.4C at Ashburton, 19/1/1956. However, on the 7th most stations in Canterbury exceeded this value, and a new record of 42C was established at Christchurch, Rangiora and Jordan (Awatere valley). New station records were also established in parts of Marlborough, Nelson, Hawkes Bay and Gisborne.

[Some maxima: 37.7 (Oamaru Aero), 39.0 (Waimate), 39.8 (Timaru Aero), 40.4 (Lincoln), 41.6 (Christchurch Gardens), 42.4 (Rangiora), 41.3 (Ashburton), 37.1 (Hanmer), 42.3 (Jordan), 37.8 (Blenheim Aero), 36.3 (Nelson Aero), 39.2 (Ruatoria – North Island record).]

Sunshine: Sunshine was mainly 30-70 hours above normal. Records were broken at Auckland with 267 hours and Nelson with 281. However, sunshine was only about normal in eastern bay of Plenty with Gisborne and Hawkes Bay, and also in parts of Otago and Southland.

[Some totals:  Kaitaia 228, Kerikeri 238, Whangarei 240, Leigh 262, Auckland 267, Tauranga 261, Whakatane 232, Taupo 241, Opotiki 206, Auckland Aero 243, Hamilton 243, New Plymouth Aero 257, Masterton 270, Gisborne 202, Napier 240, Wairoa 224, Paraparaumu 218, Ohakea 255, Kairanga 235, Palmerston North 217, Levin 209, Wellington 249, Stratford 253, Ohakune 255, Wanganui 261, Takaka 283, Westport 226, Hokitika 193, Greymouth 181, Haast 199, Riwaka 292, Nelson 281, Blenheim 289, Grassmere 266, Kaikoura 229, Mt Cook 200, Mt John 286, Methven 229, Christchurch 210, Tekapo n/a, Timaru 190, Waimate 179, Omarama 258, Palmerston 182, Dunedin Aero 174, Dunedin 155, Oamaru 194, Queenstown 231, Alexandra 232, Invercargill 165, Raoul Is 150, Campbell Is 59, Chatham Is 142].

Sources: NZ Met. Misc. pub. 107 (Climatological table, NZ Gazette) and NZ Met. Misc. pub. 109 (Meteorological Observations).

0.1C is a very small increment, and the quotes of joint records are rounded ones. Ch'ch Gardens also join the 42C club when rounded, though that's pushing things a bit.

Quite possible I think. The Jordan instrument was not being maintained or read regularly for some time prior to that day, but appeared to be in good condition, and the site had a track record of getting some very high summer maxima.

No, very uncommon. Actually in my update pending shortly for this report I have Dannevirke off the list, not because of this reading but because in the overall record there are some inconsistencies and I also want to rebalance the list a little geographically to some degree - although there are few long term sites that don't have some issues at some point in their history.

Edit: minor updates done.