Another 'atmospheric river' expected to hit B.C. as province deals with flooding from 1st

VANCOUVER -

A second "atmospheric river" in a period of about a week is scheduled to hit the still-flooded province of British Columbia, this time along the North Coast.

In light of the devastation caused by last weekend's storm - which was also an atmospheric river - across southern B.C., the provincial government is warning residents to "get prepared for heavy rain and strong winds."

Environment Canada warned of hazardous winter conditions in a warning updated Sunday morning, including heavy snow in inland sections of the region. 

The snow is expected to change to heavy rain as the temperature rises. This means that in addition to the precipitation, flooding is possible due to the melting snowpack.

"Landslides could occur," meteorologists warned, especially in the Stewart area where there have been several heavy snowfalls already this year. According to Environment Canada, 20 to 30 centimetres has already fallen since Saturday, and another two to four centimetres were expected Sunday, before strong, warm winds from the south begin to melt that snow.

Localized and widespread flooding are possible.

The weather agency expects snow to continue through Sunday morning, switching to heavy rain which will last through Monday.

The area is under a winter storm warning for the conditions described above, but there is also a rainfall warning in effect for the North Coast's inland region, including Kitimat.

An "atmospheric river" will dump up to 100 millimetres of rain on some spots, and flash flooding and water pooling is possible, along with localized flooding in lower-lying areas, the warning says.

These warnings have not been issued along the coastline, but a wind warning and special weather statement were issued Sunday morning, downgrades from previous weather forecasts for the region.

Areas including Haida Gwaii and a stretch from the north to central coasts should expect winds of 90 km/h, with even stronger gusts of 110 km/h, the national forecaster warned Sunday.

"Damage to buildings, such as roof shingles and windows, may occur. Loose objects may be tossed by the wind and cause injury or damage," the wind warning read.

As with inland sections, the coastal region should also expect to see effects of the overhead atmospheric river, though that area is under a statement, not a warning.

An area including Haida Gwaii and Prince Rupert should expect heavy rain Sunday and Monday, with rainfall amounts up to 40 millimetres and 90 millimetres, respectively.

As with locations further east, this area is warning that landslides are possible, as is flooding.

This atmospheric river is the second such event to hit B.C. in a period of about a week. Further south, a similar storm last weekend and into Monday left parts of the southern half of the province underwater, and major routes buried in mud.

At least four people died in one of multiple landslides that occurred as a result of the storm.

The incoming weather system is expected to turn south, hitting the coastline on Monday, but provincial officials said it will be in a "weakened state" at that time. But with some areas still dealing with flooding, officials are keeping an eye on the forecast and crews and equipment are on standby.

Additionally, the province's deputy premier said Saturday that Environment Canada is working on a new ranking system for the weather pattern, which will help the public know what to expect of the phenomenon making recent headlines. 

It will be an approach based on an existing system south of the border.

Atmospheric rivers are long, high plumes of moisture-laden air that can bring hours- or days-long rainfall of varying intensity to the west coast of North America.

Officials say the weather pattern is becoming more common due to climate change.

With files from CTV News Vancouver's Ian Holliday and The Canadian Press