It is common knowledge that the West Coast is often referred to as the Wet Coast, for most months of the year this is often true, however what you may not know is that during the winter months the West Coast has some of our clearest and most beautiful days of the year!
During the Winter months when temperatures are cooler the West Coast is often basking in sunshine with beautiful blue bird days. This occurs because the weather that typically brings the rain to the West Coast is the warm Nor’wester, the predominant wind in New Zealand. The reason this wind brings the rain is contributed to by several factors…
- The Nor’west wind that travels across the Tasman sea has already passed over Australia, because Australia is such a large dry continent this heats the air temperatures up, then as this warm air travels across the Tasman on its way to New Zealand, it picks up a lot of moisture which it is evaporating off the Tasman sea and drawn up into the atmosphere.
- The second factor that contributes to the rainfall on the West Coast is the mighty Southern Alps which are being thrust upward due to the collision of the two giant tectonic plates. The majority of the Southern alps are situated on the Pacific Plate which is trying to move West, but it is colliding into the Indo Australian Plate preventing the flow and as a result of all the pressure the surface of the plate is then thrust upwards causing the magnificent Southern Alps.
- As the warm air off the Tasman reaches New Zealand and the Southern Alps, it is then forced upwards and over the mountains, this is called Orographic lift, which is basically, as the air rises into the higher atmosphere, it begins to cool down and condense and turn into precipitation (the rain, snow and ice that falls from the sky)
This is why during the Winter months as the Nor’west air flow slows and is typically not as warm as during the other Seasons there is a lot less moisture coming across from the West and therefore reducing the amount of rain that we get.
To hear more in depth detail into these processes and why they occur, come and join us for a paddle on Lake Mapourika by booking your tour TODAY.
We look forward to seeing you out there!