In the 52 days between May 1 and June 21, Wellington had 27 days of southerly winds, with 16 of those days wet.
In the same period last year Wellington had 20 southerly days and three fewer wet days.
"Data confirms the talk of the town that Wellingtonians have been experiencing a sustained southerly assault so far this winter," MetService spokesman Bob McDavitt said.
Wellington was also the hardest place to play weekend sport with consistently wet weekends since the start of May, he said.
Icy winds were less frequent in the other main centres with Dunedin having 17 days of southerly winds while Christchurch and Auckland had 13.
Temperatures had begun to level out after a "sharp dive" last month but the coldest period was yet to come, Mr McDavitt said.
