May 1979:  Pressures were near normal over New Zealand and higher than usual to the south of the country. Northwest winds were slightly more frequent than usual over the north of the country, and there was a greater frequency of southwesterly winds in the south. Throughout most of New Zealand, it was a wet, cloudy month with cooler temperatures than normal. Heavy hail in eastern areas of Bay of Plenty on the 15th damaged fruit crops, and smashed windows at Thornton. In some areas hail drifts were 15cm deep. Grass growth in most districts was good at the beginning of the month but cooler temperatures later slowed growth.

Rainfall: The only areas with rainfall below normal were Northland, Auckland, parts of Bay of Plenty, Poverty Bay, Hawkes Bay, inland Wairarapa and Nelson. Some localities in Hawkes Bay and Nelson were more than 50% below normal. The wettest areas were parts of Canterbury, Otago, and Southland, where more than double the usual totals were recorded. At New Plymouth flooding occurred on the 13th when a severe thunderstorm in the morning was followed by torrential rain in the early evening, with 41mm between 6pm and 7pm.

On the 14th cars and buses were stranded on the Te Anau-Milford road when the Southland region experienced heavy rain and snow. Invercargill had 48mm in the 48 hours to 9am on the 16th, with flooding at the airport. Some stations in Southland had between 50mm and 100mm in that period.

Some totals: New Plymouth Aero 262mm, Kelburn 228mm, Wainuiomata 322mm, Stratford Mountain House 965mm, Westport 348mm, Ashburton 172mm, Invercargill 147mm; Leigh 45mm, Napier 39mm.

Temperatures: Apart from Northland, Nelson, and parts of Auckland, Bay of Plenty, Taranaki, Manawatu and Wairarapa, temperatures were generally below normal by almost 0.5C. The first two weeks were slightly warmer than usual, but from the 17th to the 24th daytime maxima were below normal by 5C or more in eastern districts.

25.3C maximum at Whangarei on the 10th, -8.5C minimum at Ophir on the 23rd.

Sunshine: The only districts with above normal sunshine hours were on the West Coast and parts of Northland and Bay of Plenty. Some areas in the northern half of the North Island were only slightly below normal. The greatest departures were in the Wellington and Southland regions. Kelburn’s 84 hours was its equal second lowest (1968) since 1942 (67 hours). Invercargill had just 59 hours.

[Some totals: Kaitaia 142, Dargaville 113, Leigh 138, Auckland 129, Tauranga 136, Whakatane 167, Rotorua 144, Taupo 103, Hamilton 107, New Plymouth 137, Masterton 93, Gisborne 137, Napier 141, Paraparaumu 97, Ohakea 119, Palmerston North 81, Wellington 84, Stratford 101, Wanganui 110, Westport 114, Hokitika 132, Greymouth 117, Riwaka 133, Nelson 136, Blenheim 133, Kaikoura 107, Mt Cook 79, Methven 109, Christchurch 112, Tekapo 115, Timaru 108, Oamaru Aero 108, Palmerston 97, Dunedin 71, Queenstown 70, Alexandra 94, Gore 75, Invercargill 59.]

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