CLIMATOLOGICAL TABLE--Summary of the Records of Temperature, Rainfall, and Sunshine for June 1973--continued

The "normal" refers to the present site of the instruments. Standard periods for normals are: Temperature 1931-60, Rainfall 1921-50 Sunshine 1935-60. No normals are available for stations with only short records.

*Indicates that the sunshine recorder is not located at the station but is in the near vicinity.

A rain day is a day with rainfall equal to or greater than 0.1 mm.

Where the extremes of temperature and rainfall have occurred more than once during the month, the date of the first occurrence is given.

NOTES ON THE WEATHER FOR JUNE 1973

General

June was a mild month. There was an unusually high frequency of north-easterly winds in the North Island and of northerly winds in the South Island, causing wet conditions in Northland, Gisborne, and Hawke's Bay but dry, relatively sunny conditions in Canterbury, Otago, and Southland. The mildness was appreciated by farmers, who reported good growth still over the greater part of the North Island. However, in parts of Nelson, Marlborough, and Canterbury conditions were too dry, as in previous months.

On the other hand, rainfall was above normal in most northern and eastern districts of the North Island, and in parts of the Southern Alps.

Temperatures

Temperatures were above normal, mainly by 1°C. Highest departures were recorded in the North Island. The mildest periods were from the 2nd to the 9th and from the 24th to the 26th.

The lack of snow on the ranges was very noticeable, especially in the South Island.

Sunshine

Southland, Otago, Canterbury, and the greater part the West Coast were favoured with 20-50 hours more sunshine than normal. Invercargill's total of 97 hours was the second highest recorded there in June in over 40 years of observation.

Over the remainder of the country sunshine was mainly about normal.

Weather Sequence

At the beginning of June an anticyclone was centred to the east of the North Island, extending over New Zealand and the eastern Tasman Sea, with fine weather. On the 2nd a small depression west of Northland caused some rain there and in Auckland. During the following 3 days a trough extending from north to south, associated with a depression far to the south of Campbell Island, moved slowly eastward over the country, becoming stationary near Auckland. There was general rain with the passage of this trough, including some considerable falls on the West Coast, and in Taranaki, Bay of Plenty and Northland. Temperatures remained mild. As the trough moved off eastward on the 6th and another one was approaching the South Island from the west. rain persisted over most of the North Island and also on the West Coast.

On the 7th and 8th this trough commenced to cross New Zealand. It was associated with a depression just west of Southland and a second centre soon developed over the north Tasman Sea. Rain persisted in the west of both Islands while temperatures remained mild. During the following 2 days this northern centre moved on to Northland from the west, causing considerable rain over the North Island, especially in northern districts, while a south-westerly change with cooler temperatures affected the South Island. On the 11th, with the depression off the coast of Hawke's Bay, colder south-westerly conditions spread to the North Island with showers, except in a few eastern districts. Some western and southern districts of the South Island were also still having showery periods, as in the previous 2 days. On the 12th an anticyclone centred east of the North Island brought generally fine weather.

During the 13th and 14th a large depression over the north Tasman Sea moved south-eastward across the North Island, causing considerable rain, mainly over the North Island. The rain was particularly heavy in Gisborne and northern Hawke's Bay; in the ranges falls of 200 mm were reported over the 2 days. By the following day the depression had departed well to the east, and cold south-easterlies covered the country with showers from Christchurch to East Cape. On the 16th and 17th pressures remained low to the east, while another depression was moving eastward to the north of Northland. Showers persisted on the east coast of the North Island and rain was now reported in Northland.

From the 18th to the 22nd an anticyclone over the south Tasman Sea moved slowly across New Zealand to the east. This provided a welcome spell of fine weather, particularly in the North Island, but conditions were rather frosty.

During the next 2 days a trough of low pressure associated with a depression far to the south moved eastward over the country, bringing rain to the West Coast, besides Northland, Bay of Plenty, and Auckland, which were affected by a depression to the north. On the 25th a complex trough associated with another depression far to the south moved on to the country with fairly general rain except in eastern districts from Balclutha to East Cape. Temperatures had become mild once again. On the 26th a small wave formed on this depression near Cook Strait and rain became general with considerable falls about Wellington. As the trough moved away during the following 3 days colder south-westerlies prevailed, with showers in Fiordland, Southland, and Otago, and also at first in many parts of the North Island. On the last day of the month an anticyclone over the south Tasman Sea moved on to the South Island. The increased southerly flow caused cold, showery conditions in Southland, the Christchurch area, the east coast of the North Island, and about Cook Strait.

J. F. de LISLE, Acting Director.

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