In New Zealand, the weather is dominated by the passage of high-pressure systems
(anti-cyclones and ridges) and low pressure systems (depressions and troughs).
These usually move from west to east across the country.
In New Zealand, the weather is dominated by the passage of high-pressure systems
(anti-cyclones and ridges) and low pressure systems (depressions and troughs).
These usually move from west to east across the country.
Weather maps are usually printed in most daily newspapers (eg: The Press). The maps will contain a key to aid in the interpretation of the symbols. Note that "troughs" or "fronts" can result in sudden changes of weather.
Notwithstanding the general pattern that one is able to obtain from the maps, New Zealand’s topography results in markedly varied weather conditions within localised areas. Find out about local conditions and idiosyncratic weather patterns if unsure.
Learn to interpret maps by reading them regularly at home; - try predicting the weather yourself.
Wind: The strength and general direction of the wind can be determined from the weather map. The prevailing wind in New Zealand is generally from the NorthWest.
Wind flow is anti-clockwise around a high-pressure system (anti-cyclone).
Wind flow is clock-wise around a low-pressure system (depression)
The spacing of the Isobars will give an indication of possible wind strength. Generally, the closer the spacing between the isobars, the stronger the wind.
In New Zealand, a Southerly Wind or front will usually result in colder air moving onto the country. Snow may fall at higher altitudes, regardless of the season.
New Zealand’s mountain ranges have a large influence on localised effects of the weather. Gaps in the main divide will usually result in a higher prevalence of stronger winds (eg Wellington and Cook Strait). Areas east of the main divide are generally drier in the usual prevailing conditions.
Temperature: As a general rule, air temperature drops by between 6.5 degrees and 10 degrees Celsius per 1000m increase in altitude. A hike above the bush-line (usually between 1000m and 1300m) can therefore result in conditions where the temperature is about 8 to 10 degrees less than that at sea level. Stronger winds at the higher altitude can increase the cooling effect of the wind.
The New Zealand Meteorological Service operate an 0900 forecast service (the caller pays a fee to receive a forecast). Details are in local phone books and newspapers.