The NIWA and MetService assessment of named tropical cyclone (TC) activity indicates 8 to 10 named TCs could occur in the Southwest Pacific basin between November 2020 and April 2021. This seasonal outlook is for normal to below normal activity in terms of overall named cyclone systems in the region.
The NINO3.4 Index anomaly (in the central Pacific) during May (through the 30th) was -0.11˚C, the smallest anomaly since July 2020. The Southern Oscillation Index (SOI) was +0.5, in the ENSO neutral range.
Temperatures are most likely to be above average in the west and east of the South Island and about equally likely to be above average or near average in all other regions. While cold spells and frosts will occur, as is typical during winter, they may be infrequent.
Temperatures are very unlikely to be colder than average for the three months as a whole. Above average or near average temperatures are favoured for all regions except the east of the South Island, where above average temperatures are most likely.
When high winds on the Auckland Harbour Bridge last September caused two trucks to topple over, one into a load-bearing strut, NIWA scientists began thinking about what role they could play in preventing it from happening again.