New Zealand: Severe weather forecast across parts of western South Island and southern and western North Island through at least Nov. 17 /update 1

Severe weather is forecast across parts of western South Island and southern and western North Island through at least Nov. 17. A series of weather fronts are forecast to move across the country from the Tasman Sea late Nov. 16-17, bringing heavy rainfall and strong winds to affected areas. Rainfall totals of 6-12 cm (2.4-4.7 inches) are forecast in elevated areas of the affected regions.

As of late Nov. 16, the New Zealand National Meteorological Service (MetService) has issued the following weather warnings:

• Orange Heavy Rain Warning (middle level on a three-tier scale): Mount Taranaki, the Tararua Range, and the ranges of Westland south of Otira.

• Yellow Heavy Rain Watch: Buller about and north of Westport, and Tasman west of Motueka, and Fiordland north of Doubtful Sound.

• Yellow Strong Wind Watch: Northern Marlborough, Wellington, and Wairarapa excluding Tararua District.

Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are likely where significant flooding or landslides impact utility networks.

Floodwaters and debris flows will likely render some bridges or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces will likely cause hazardous driving conditions on regional highways. Authorities are likely to temporarily close some low-lying routes that become inundated by floodwaters. Flight delays and cancellations at airports are probable.

Localized business disruptions are likely in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.