NZ Weather Forum

Hello. I'm thinking about southerly air flows in the South Island. How do they differ from sou-westerlies. Is it to do with the part of the island you are in, for instance does a steady southerly flow that strikes the bottom of the island get shifted and turned into the dreaded Dunedin sou-wester? Or does the sou-wester begin well before the island? And also, in a typical year, how many pure southerly flows would hit the bottom of the S.I?

A southerly affects the east coast but a SW blows it guts here and keeps the east coast clear and often the westcoast SI

The traditonal flow is the south-wester but then it can be tilted and deflected according to orographical landform.
Also, a low forming on a cold front moving up in a SW airstream, can tend the surface wind to a more southerly direction or even further around to a SE windflow.
JohnGaul
NZTS