what does la nina mean in the mountains?

[tramper]

Looking for advice out there, I'm wanting to do a month long traverse from arthurs pass to mt cook along(or next to) the spine of the alps, and wondering if this january with the influence of the la nina is going to be wetter or drier than normal, I'm a bit confused and read wetter in north island, possible drier in canturbury...but in the mountains? any ideas anyone? help or ideas would be appreciated, cheers.

[spwill]

the spine of the alps, and wondering if this january with the influence of the la nina is going to be wetter or drier than normal,

With la nina there tends to be less westerly flow and more NE flow onto NZ so it should be drier for the Southern Alps but probably more cloud along the SouthIsland east coast.

[NZstorm]

NOAA in their November La Nina update expect strong La Nina conditions from October to January. That prediction indicates rainfall will be down over the Southern Alps with a tendency to more settled weather as well. They expect La Nina to persist into mid 2011.

[tramper]

maybe sounding like an ideal season for mountain traverse? walked a different route arthurs pass to cook feb 08( in fact the whole south isalnd dec 07 - march 08), heard it was a 'drought' year, conditions ideal, was that a la nina pattern?

[NZstorm]

walked a different route arthurs pass to cook feb 08( in fact the whole south isalnd dec 07 - march 08), heard it was a 'drought' year, conditions ideal, was that a la nina pattern?

yes, that was a La Nina season.

[Captain Salty]

anything easterly is usually good in the mountains. Often the most settled conditions inland and a break from the prevailing westerlies. That is my experience in the Arthur's Pass area anyway.

This website covers current conditions http://www.softrock.co.nz/mg/index.php

[RWood]

Generally it looks like a good bet, especially if the La Nina is reasonably strong. There have been some exceptions at all levels of strength though, particularly in early summer: Dec 1984 and Jan 1985 were wet in the high country and Westland/Fiordland (moderate La Nina); in the strong 1988/89 event, December 1988 was wet in Fiordland, and in the weak La Nina of 1995/96, December 1995 was exceptionally wet in the Alps and Westland, with a record 2927mm rainfall at the Cropp River "Waterfall" site.