JULY 26.] THE NEW ZEALAND GAZETTE. 2285

The weather from the 6th to the 11th, during which such widespread and, in many places, heavy rain fell, was of a very unusual type. On the 4th a small but rather intense anticyclone was centred over Otago, and owing to the steep pressure gradients to the north-eastward, strong southerly winds, reaching gale force at many places, blew from Cook Strait northwards. The characteristics of this anticyclone suggested some unusual activity to the east or north-east. During the 5th and 6th a southern depression advanced over the South Tasman Sea and crossed the Dominion with much decreased intensity, rain setting in over the southern districts. This was followed by a feeble anticyclone. On the 7th a shallow cyclone was centred over the Tasman Sea. From this point onwards northerly or north-easterly winds set in over the New Zealand area, and the period of unsettled weather commenced. Pressure began to rise over, and especially to the eastward of, New Zealand. The unusual phenomenon was therefore experienced of northerly winds and wet weather accompanying a rising barometer. The cyclone from the Tasman Sea crossed the South Island on the 9th, but was so shallow as to be scarcely recognizable on our charts. The heaviest rain occurred on this day. After the passage of the cyclone there was a further rise of pressure which reached 30·63 in. at Chatham Islands on the 11th. Winds continued northerly. Throughout the period it was evident that some other influence than the usual march of pressure systems from the westward was exercising a control over the weather. The sources of this influence were probably in the regions to the east of New Zealand. The very mild conditions combined with the heavy rains led to a rapid growth of grass.

A somewhat similar condition followed in the period from the 12th to the 16th. Northerly gales were experienced on the 12th to the 14th, while an intense southern depression was advancing over the South Tasman Sea. This depression filled up on crossing the Dominion as did that of the 6th, and following it pressure was again high at Chatham Island. A cyclone then developed in the Central Tasman Sea and crossed Canterbury on the 16th. Rains were once more widespread with many heavy falls. In the Cook Strait region, the rate at which the rain fell on the 16th was remarkable. At one stage 20 points were recorded in six minutes at Wellington, and in a space of one hour 74 points fell. There were northerly gales on the 16th.

On the 21st, following the passage on the 20th of a southern low-pressure wave, which deepened when in the neighbourhood of Chatham Island, there were strong south-westerly winds to gales, and rain fairly general except in some of the eastern districts.

A rather intense cyclone crossed the southern portion of the South Island on the 26th and 27th, causing general rain. This was followed by the development of a second cyclone in the Northern Tasman Sea, which increased in intensity and advanced eastward. This cyclone was west of Auckland on the 30th, and caused general rain with very heavy falls in all northern districts and heavy falls in many other parts, especially in eastern districts. In the twenty-four hours subsequent to 9 a.m. on the 30th, the barometer fell over an inch at many places from Wellington southwards. Severe gales blew on this day. The direction was between east and north-east at most places, but was deflected to south-east in parts of Cook Strait. The severity was greatest in the Auckland Province, where much minor damage was done to shipping, buildings, telegraph and power lines, &c. Smaller damage was done in other centres, including Wellington, Christchurch, and Dunedin.

EDWARD KIDSON, Director.

CLIMATOLOGICAL TABLE.
MEANS AND TOTALS FROM CHIEF STATIONS.
April, 1928.