New Zealand: Severe weather forecast across western parts of South Island through at least Nov. 9

Severe weather is forecast across western parts of South Island through at least Nov. 9. A weather front is expected to bring exceptionally heavy rainfall across the region over the coming days. Rainfall totals of 30-45 cm (12-18 inches) with localized higher amounts are expected in the ranges of Westland District Nov. 8-9, with lesser amounts in coastal areas. The heavy downpours may trigger flooding in low-lying areas and landslides on unstable slopes.

As of late Nov. 6, the New Zealand National Meteorological Service (MetService) has issued the following weather warnings across the affected area:

• Orange Heavy Rain Warning (the middle level on a three-tier scale): Westland District.

• Yellow Heavy Rain Watch: Fiordland about and north of George Sound.

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 located 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 hours. Where significant flooding or landslides impact utility networks, disruptions to electricity and telecommunications services are possible.

Floodwaters and debris flows will likely render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces will cause hazardous driving conditions on regional highways. Authorities will probably temporarily close some low-lying routes that become inundated by floodwaters. Severe weather will likely trigger flight delays and cancellations at regional airports. Flooding will probably block regional rail lines; freight and passenger train delays and cancellations are likely in areas with heavy rainfall and potential track inundation.

Localized business disruptions are probable 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.