'River in the sky' forces thousands to evacuate as floods hit California, leaving 2 dead

• A "river in the sky" has poured down on California, causing flooding.
• 2 people have died in the extreme weather.

An atmospheric river, which the National Oceanic and Atmospheric Administration compares to a "river in the sky," has poured down on California, forcing thousands to evacuate.

The extreme weather caused the Pajaro River's levee to breach, leading to 8,500 evacuation orders in Monterey County on the Pacific coast.

The California Governor's Office for Emergency Services states that an evacuation order is "mandatory" and an "official order to leave," as the conditions are considered a threat to life.

According to AP, evacuation officials had called on homes on Friday to encourage residents to evacuate. They had to pull some of those who refused from floodwaters on Saturday.

First responders and the California National Guard had to save over 50 people overnight from the water overnight, AP reports.

At least two people died on Friday as a result of the harsh weather conditions, with one person being killed after a portion of the roof collapsed at an Oakland warehouse, according to the LA Times.

But the worst isn't yet over. Approximately 15 million people are under flood watches in California and Nevada as a second "river in the sky" approaches, CNN reports.

The National Weather Service has said that the worst of the storm is predicted to come late on Monday through to early Tuesday, although heavy rainfall has already seen thousands be given evacuation orders.

According to the Weather Prediction Center, from Monday night, "the rain will impact increasingly sensitive portions of central California that were hit hard by the rainfall on Friday and early Saturday," said. They added that it "won't take long once the steady heavy rain gets started for flooding impacts to resume."