July 1977: During July pressures were near normal in the North Island and on the West Coast, but considerably higher than normal at Campbell Island. There was a marked absence of westerly winds, and for the second month in succession a predominance of winds from an easterly quarter. Apart from southerly gales on the 3rd & 4th winds were unusually light throughout the month. This was a cloudy month over most of the country, especially on the east coast of the South Island. Gales and rain on the 3rd-4th caused severe flooding in the Christchurch and Banks Peninsula areas, and many transport services were disrupted throughout the country. Thick fog over most of the country on the morning of the 14th and 15th closed the major airports. The only areas with dry ground conditions were parts of Westland, Fiordland, Central Otago and Southland.
Rainfall: Rainfall was above normal over the northern half of the North Island, Manawatu, southern Wairarapa, Wellington, and the east coast of the South Island. Some stations in Fiordland and Central Otago were 75% below normal. On the 3rd-4th nearly 49mm was recorded at Christchurch Airport in 12 hours and the 24 hour total to 9am on the 24th was 77mm. The total fall for the month there was nearly 200% above normal, and in the city more than 250% above. Heavy rain on the 19th, 20th and 21st caused flooding in many areas of the North Island. The Coromandel Peninsula, Northland, Hauraki Plains, and the Gisborne area were worst affected. Coromandel station recorded 175mm in 48 hours, and the following 24 hour totals were recorded in other parts of the North Island: Whangarei 141mm, Waihi 120mm, Thames 99mm and Rotorua 82mm.
Some monthly totals (mm): Whangarei 254, Paeroa 281, Hamilton 188, New Plymouth 223, Kaikoura 197, Christchurch 209, Oamaru Aero 102, Dunedin 117; Reefton 59, Milford 84, Coleridge 30, Tekapo 10, Queenstown Aero 9, Invercargill 30,
Campbell Is 37 (2nd lowest).
Temperatures: Mean temperatures were above normal over most of New Zealand, in Bay of Plenty, Nelson, and Central Otago by more than 1C. A few isolated areas in both islands were below normal, but none by as much as 0.5C. The coldest spell was the 3rd and 4th, with a southerly airstream over the country.
20.4C maximum at Waiau Oyster Point on the 1st,
-9.1C minimum at Ophir on the 16th.
Sunshine: This was a cloudy month over the whole of New Zealand with the exceptions of parts of southern Hawkes Bay, Buller, and Westland. Christchurch, Ashburton, Timaru and Dunedin recorded their lowest sunshine hours for any month since recordings started. These stations were below the monthly average by as much as 60 hours. [Still the lowest values for July at these sites].
[Some totals: Kaitaia 133, Waitangi 137, Whangarei 132, Auckland 124, Tauranga 118, Whakatane 126, Rotorua 107, Taupo 94, Hamilton 108, Te Kuiti 86, Taumarunui 81, New Plymouth 131, Masterton 75, Dannevirke 94, Gisborne 116, Napier 132, Wairoa 122, Paraparaumu 96, Ohakea 115, Palmerston North 110, Levin 104, Wellington 84, Stratford 106, Wanganui 103, Westport 125, Hokitika 127, Greymouth 114, Riwaka 128, Nelson 134, Blenheim 132, Grassmere 107, Kaikoura 87, Mt Cook 78, Mt John 121, Methven 79, Christchurch 61, Tekapo 104, Timaru 60, Oamaru Aero 68, Omarama 98, Palmerston 75, Dunedin 59, Te Anau 57, Queenstown 78, Alexandra 92, Gore 92, Invercargill 70].
Sources: NZ Met. Misc. pub. 107 (Climatological table, NZ Gazette) and NZ Met. Misc. pub. 109 (Meteorological Observations).
Share Topic
February 14, 2012, 03:56:45 PM