December 1968: December was a cool month, marked by an unusually high frequency of easterly and northeasterly winds, causing cloudy and wet conditions in the east of the North Island, while the West Coast was sunny with comparatively low rainfall. Nearly all the areas where November rainfall was inadequate had good rains in December, and growth was good except in North Otago.

Rainfall: Rainfall was above average, mainly by 50%, over the North Island and in Nelson, Marlborough, North Canterbury and parts of central Canterbury. It was more than double the average in a large area extending from parts of Taihape through inland Hawkes Bay and parts of Gisborne and Bay of Plenty to Waikato; also in some areas in Northland and Nelson. Over the remainder of the South Island rainfall was below average. It was less than half the average in coastal Otago and north Westland, and less than 1/4 in the Alps, South Westland and Fiordland. Milford Sound’s 5.64” was the lowest for December in 40 years of record, and Otira’s 4.26” the lowest since 1934. [Milford lowest now 69mm in 2011].

In the Taihape district, on the afternoon of the 7th, there were many violent thunderstorms associated with a slow-moving trough. Exceptionally heavy rain over a 1 to 2-hour period resulted in large slips and washouts near Mangaweka, with road and rail traffic disrupted for several days. Waiouru recorded 1.68” of rain in an hour. Thunderstorms were also comparatively frequent over the North Island from the 23rd to the 30th.

Temperatures: Temperatures were 2F-3F below average in Northland and in eastern districts from Gisborne to Canterbury. Elsewhere they were close to or somewhat below average.

Sunshine: Sunshine was below average over nearly the whole of the North Island and in Nelson and Marlborough. In eastern and northern districts of the North Island the deficiency was 60-90 hours, with record low totals for December at Waihi and Gisborne [Gisborne’s total of 164 was lowered to 158 in 1992]. Whangarei had only 111 hours [The only lower total so far recorded in the North Island in December or January is the possibly suspect value of 104 at Palmerston North in 1992]. Most remaining districts of the South Island were favoured with 20-50 hours above average sunshine.

[Some totals:  Kaitaia 161, Kerikeri 134, Whangarei 111, Auckland 156, Tauranga 212, Whakatane 190, Taupo 159, Opotiki 174, Hamilton 177, New Plymouth 215, Masterton 136, Gisborne 164, Napier 176, Wairoa 184, Paraparaumu 217, Ohakea 203, Palmerston North 169, Levin 183, Wellington 208, Stratford 189, Ohakune 164, Wanganui 187, Westport 203, Hokitika 255, Greymouth 179, Haast 221, Riwaka 225, Nelson 223, Blenheim 196, Grassmere 178, Kaikoura 166, Mt Cook 210, Mt John 274, Methven 216, Christchurch 227, Tekapo 286, Timaru 182, Waimate 147, Omarama 218, Dunedin Aero 213, Dunedin 208, Oamaru 191, Queenstown 264, Alexandra 272, Invercargill 222, Campbell Is 101, Chatham Is 130]


Sources: NZ Met. Misc. pub. 107 (Climatological table, NZ Gazette) and NZ Met. Misc. pub. 109 (Meteorological Observations) - additional comments by the poster.

Certainly unusual to see Campbell Island have only a few hours less sunshine than Whangarei!