New Zealand: Severe weather forecast across most of the country through at least early Oct. 4

Severe weather is forecast across most of New Zealand through at least early Oct. 4. An active front over the Tasman Sea is forecast to track eastwards across the country late Oct. 1-3, bringing heavy rain over western and northern parts of the country and heavy snow for southern parts of the South Island.

As of early Oct. 1, 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): Mount Taranaki, Richmond, and Bryant ranges, including the Rai Valley, Tasman northwest of Motueka, and the Westland District.

• Yellow Heavy Rain Watch: Bay of Plenty, Buller and Grey districts, Coromandel Peninsula, Gisborne/Tairawhiti north of Ruatoria, and Northland.

• Yellow Heavy Snow Watch: Central Otago and the Queenstown Lakes District.

• Road Snowfall Warning: Haast Pass (SH6), Lindis Pass (SH8), Milford Road (SH94), and Crown Range Road.

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

Where precipitation falls as rain, flash and areal flooding are possible. This may occur in low-lying communities near watercourses and other large bodies of water and in urban areas with easily overwhelmed stormwater drainage systems. Sites downstream of large reservoirs may be subject to flash flooding after relatively short periods of intense rainfall.

Precipitation could fall as snow in the higher elevations over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in mountainous areas. Rain-induced landslides are possible in areas of elevated terrain, and avalanches are also possible in mountainous areas where snowpacks have become unstable due to heavy snowfall. Power outages are likely throughout the affected area.

Floodwaters and related debris will probably render some bridges, rail networks, or roadways impassable, impacting overland travel in and around the affected area. Flooding in urban areas will likely cause significant traffic congestion. Heavy snow will make driving hazardous in some areas; authorities will probably implement temporary road closures or detours in such locations. Officials will likely close mountain passes and tunnels as a precautionary measure during periods of intense snowfall.

The disruptive weather will probably cause delays and cancellations at airports across the affected region. Authorities will likely suspend port operations temporarily if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding/snow will probably block regional rail lines, causing freight and passenger train delays and cancellations.

Disruptions triggered by inclement weather and resultant hazards, such as flooding or avalanches, will likely persist well after conditions have improved - it could take days before floodwaters recede and/or officials clear debris. Repair or reconstruction efforts may result in residual disruptions if there is severe damage to infrastructure.