Weather
The weather in New Zealand is very unpredictable, don’t be fooled by
perfect weather as in a matter of minutes your easy tramp can turn into a
struggle against wind, rain, and snow. Look at weather forecasts before
you go:
But do not treat these as indications of what the weather is definitely
going to do. The weather can travel and change very quickly, especially in
places like fiordland where limited amounts of data can be collected about
weather systems as they come from a large uninhabited area with little sea
or air traffic.
It is worth calling into DOC offices and national park headquarters to
receive local weather forecasts, besides you should be calling in at these
place to place your intentions in any case.
Reading the Weather
Signs of approaching bad weather include increasing wind speed and the
arrival of clouds known as ‘hog’s backs’. These are the outriders of
northwesterly storms. In general, northwesterlies bring wet weather and
storms, southerlies bring cold weather followed by clear conditions,
northeasterlies indicate good weather and southwesterlies are cool,
rain-laden winds.
Climate
Because New Zealand is located in the ‘roaring forties’ latitude, it has
prevailing west to east weather system. Warm and moisture-laden wind from
the Tasman Sea hits the Southern Alps and is swept upward, cooling and
dropping its moisture. This creates a wet climate on the West Coast and a
dry one on the east (annual rainfall can vary from 7500mm on the west
coast to only 330mm on the other side of the divide, not too far away).
Wind from the south comes from Antartica and is always cold.
