A shift to westerlies means most regions should be in for a warmer week this week.  

The strengthening westerly flow will start overnight tonight in the deep south then spread north during Tuesday.  Those in the east of both islands should have relatively mild conditions as the winds becoming gusty in exposed places.

Wednesday and Thursday will see a north west flow in the North Island ahead of a low pressure system forming in the Tasman Sea.

The low is likely to bring heavy rain to western parts of the country on Thursday.

Colder southerlies or sou’westers may affect the lower South Island on Wednesday and Thursday.