1010
THE NEW ZEALAND GAZETTE
No. 38

CLIMATOLOGICAL TABLE—Summary of the Records of Temperature, Rainfall, and Sunshine for May 1966—continued

LATE RETURNS

| Waihi, Apr 1966 | 300 | 67·6 | 47·5 | 57·6 | −0·2 | 72·8 | 10 | 36·5 | 4 | 6·14 | 12 | −2·2 | 1·79 | 29 | 187 |
| Tarawera Forest, Apr 1966 | 200 | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. |
| Ohakune, Apr 1966 | 1,964 | 59·8 | 41·2 | 50·5 | +1·5 | 64·9 | 27 | 31·0 | 28 | 4·97 | 13 | .. | 1·69 | 26 | 158 |
| Foxton, Apr 1966 | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | .. | 162 |
| ERRATA
| Raoul Island, Mar 1966 | .. | .. | .. | .. | .. | .. | .. | .. | 8·22 | .. | .. | .. | .. | .. |

The “normal” refers to the present site of the instruments. The standard periods for normals are: for temperature 1931–60, for rainfall 1921–50, and for sunshine 1935–60. No normals are available for stations with only short records.

*Sunshine recorder is not located at the station but is in the near vicinity.

NOTES ON THE WEATHER FOR MAY 1966

General: Barometers were low over and to the east of the North Island during May, and there was an unusually high frequency of southerly to easterly winds. It was a cold month but conditions were particularly pleasant on the West Coast. Farmers found it a good month for stock, though in some areas growth was affected by frosts and in Northland and Auckland the ground was becoming rather too wet.

Rainfall: On the West Coast it was by far the driest May on record, with less than a quarter of the average rainfall. It was also exceptionally dry in the Alps, the Canterbury high country, and Central Otago. Rainfall was also somewhat below average in Southland and Nelson and in the North Island west of the main ranges from Hamilton and Opotiki to Levin.

In eastern districts from Oamaru to East Cape, about Cook Strait, and in Northland and Auckland rainfall was above average. The surplus exceeded 50 per cent in Wairarapa, Wellington, most of Marlborough, and the North Canterbury coast, also in Coromandel. Over most of Marlborough more than two-thirds of the month’s rain, amounting to 4–10 in. fell on the 23rd during the passage of a deep depression across the North Island. Flooding disrupted road and rail transport between Blenheim and Kaikoura.

Temperature: Temperatures were mainly below average by about 1–2 degrees, highest departures being in Manawatu. On the West Coast they were close to average.

The second half of the month was much colder than the first half. Two spells of cold southerlies brought snow to the ranges and some of the North Island high country from 17–20th and on 25, 26th respectively.

Sunshine: Northern and western districts of both Islands together with parts of Southland were favoured with more sunshine than usual, mainly by 20–30 hours. Eastern districts from Balclutha to East Cape received less than average by a similar amount.

Weather Sequence: There was widespread rain on the 1st as a depression from the North Tasman Sea crossed the North Island and another depression passed far to the south. The weather cleared over most of the South Island on the following day but remained unsettled in the north with the depression near Auckland. Rain persisted for two more days in Gisborne, Coromandel, and parts of Northland as the depression departed to the north-east; but elsewhere the weather was fine under the influence of a ridge of high pressure extending from an anticyclone over the Tasman Sea.

As this anticyclone moved slowly eastward over the country from the 5th to the 7th, isolated showers persisted in Northland and Gisborne.

By the 8th the anticyclone was centred to the south-west of the South Island and two depressions were centred to the east and west of Northland respectively. During this and the next three days the second depression moved eastward, with rain in northern districts, also in Gisborne and Hawke’s Bay, and light falls later in other eastern districts. During the 12th and 13th another depression from the Central Tasman Sea crossed Northland. Rain persisted in northern districts and spread to some other areas, including parts of the South Island.

A spell of generally fair weather was experienced on the 14th and 15th with a ridge of high pressure over the South Island, except for some deterioration on the West Coast and in Southland late on the 15th with the approach of a trough of low pressure.

The trough crossed the country during the 16th and 17th with fairly general rain, soon clearing however over most of the South Island with the advance of a ridge of high pressure. Southerlies developed over the North Island and temperatures became colder, with snow on the high country. These cold southerlies persisted for three more days as a depression formed to the east and remained stationary near the Chatham Islands. Rain affected most eastern districts from Christchurch to East Cape (except for parts of Hawke’s Bay) and also the area about Cook Strait. However, a ridge of high pressure extending from the north brought better weather on the 21st.

From the 22nd to the 24th a depression from the North Tasman Sea crossed the North Island with widespread rain except on the West Coast. Some very heavy falls were recorded in Marlborough, with flooding on the Kaikoura coast. For the next two days the depression remained almost stationary east of Hawke’s Bay and cold southerlies brought rain to most eastern districts and the Cook Strait area and snow again to the high country. From the 27th to the 29th the depression moved southward, another trough crossed the country, and a second centre developed north-east of East Cape. There was some more general rain, followed by cold southerlies once again with rain mainly about Cook Strait and in Northland.

The last two days of the month were favoured with improved weather as an anticyclone moved on to the North Island.

J. F. GABITES, Director.

(N.Z. Met. S. Misc. Pub. 107).