The climate of the Cromwell basin is dry and marked by hot summers and cold winters. These continental characteristics are caused by the presence of high mountain barriers to the west. There are three distinct climatic zones that appear between Cromwell and Lake Hawea. First, from Lake Hawea/Maungawera location is a zone of Subhumid to Humid with moisture adequate at all seasons. Second, the area encompassing Wanaka to Luggate and Queensberry, is a Subhumid area with moisture deficiencies at all seasons. Thirdly, the area from Queensberry to Cromwell is termed Semi-arid with moisture deficiency at all seasons.
The Semi-arid Cromwell basin indicates rainfall of about 406mm pa with 55% falling in the summer months between October and March, when high evaporation tends to render it least effective. Conversely, although June, July and August have the lowest rainfalls, the soil moisture content is greatest because of the lower evaporation. Because of the dry climate, extensive use is made of irrigation especially in horticulture, civic +facilities and house gardens.
Temperatures are also markedly continental in character. The average mean annual temperature is 10.7ºC, but the range is considerable by New Zealand standards with a maximum recording of 36.6ºC in January and minimum -9.2ºC in June, July and August. Ground frosts can occur any month and an average 174 are expected yearly. Humidity is low (67 per cent) and only occasional snowfalls are recorded in winter months. The prevailing winds are from the north, nort-east and north-west, but a number of southerly winds are also experienced.
CROMWELL CLIMATE data (annual averaged figures from 50 years of data)
Rainfall
406mm (over 68 days with fall of 1.0mm or more)
Temperature
Yearly: mean 10.7°C,
January: mean 17.6°C / max. 36.6°C
July: mean 2.9°C / max. -9.2°C
Average ground frost days
174 per year
Average wind speed
11.8km/h
Thunder
2.5 mean days
Gale Force Winds
0.3 days
Fog
23.8 days
Hail
0.5 days
Lightning
2.5 days
Snowfall
3 days
Cromwell... a land of contrasts!
Long, hot summers that soar into the mid 30°C, warm breezes, the sparkling waters of Lake Dunstan, the pretty wild flowers lining the roads. Parched mountains of rock and tussock.
The fiery colours of autumn leave an indelible memory in your mind as you wander through fallen leaves along a county path.
The winter snows arrive and turn the mountains from dark blue to white as you sip local wines around the roaring log fire at a local pub.
The blossoming of spring and the greening of willows and poplars remind you that there is always a time to consider a fresh look at life.