The MetService says severe northwest gales could gust to 120kmh from 6pm today until 7am tomorrow in Southern Lakes, Central Otago, North Otago and Dunedin.
''Driving may be hazardous, especially for high-sided vehicles and motorcycles,'' a MetService spokesman said.
He urged residents to secure anything that could be picked up by wind.
Firefighters warned that severe gales also increased the danger of fires.
Southland principal rural fire officer Timo Bierlin and Otago district principal rural fire officer Graeme Still said fire permits for both regions had been cancelled until further notice.
Mr Bierlin said the strong northwest gales would bring warm, dry conditions to Southland, significantly increasing the risk of fires occurring and spreading rapidly.
''We are asking people not to light fires while these conditions persist.
''Activities such as welding, grinding, chainsaw use, or mowing roadsides could all have the potential to start a fire during dry conditions.''
He also asked people who had burnt fires in the past two months to ensure they were out.
Fire and Emergency New Zealand asked people to extinguish any burning fires, and not to light any more - including solid fuel barbecues, camp fires, incinerators and hedge trimmings - until conditions had eased.
