A major power grid that spans 14 states, from North Dakota to Texas, has ordered rolling blackouts amid an extreme cold blast that has hit the south.

Southwest Power Pool (SPP), which is headquartered in Little Rock, Arkansas, ordered the rolling blackouts on Monday, declaring an energy emergency. Extreme weather had already taken out power for millions of homes in Texas, where temperatures hit record lows.

The grid operator said in a statement on Twitter that this was the first time it's ordered mass rolling blackouts, and that it was doing so to prevent further uncontrolled outages.

"It's a last resort, that we understand puts a burden on our member utilities and the customers they serve, but it's a step we're consciously taking to prevent circumstances from getting worse, which could result in uncontrolled outages of even greater magnitude," SPP's executive Vice President and chief operating officer Lanny NIckell said in the statement.

SPP isn't alone in ordering rolling blackouts due to the winter storm.

Electric Reliability Council of Texas (ERCOT) issued rolling blackouts in Texas on Monday, and power provider Oncor told customers that the supply of electricity was "lower than demand." The cold snap also caused T-Mobile outages in the state.

On Monday, at least 2.8 million Texans had experienced power outages, according to PowerOutage.us.

Dan Woodfin, a senior director for the Electric Reliability Council of Texas, which manages the state's power grid, said in a press conference that outages were expected to continue into Tuesday, per Bloomberg.

"We anticipate we will need to continue these controlled outages for the rest of today and perhaps all day tomorrow," he said.

Bill Magness, head of the Electric Reliability Council of Texas, told Bloomberg that all grid operators and electric companies in the state were "fighting to restore power" as soon as possible.

Extreme cold weather and snow are rare in Texas, and the National Weather Service in the state, based in Midland, tweeted early Monday that it recorded a temperature of minus 2 degrees Fahrenheit, the coldest temperature in the region in 32 years.

All 254 Texas counties were under winter weather advisories as of Sunday night, and President Joe Biden declared a state of emergency, giving Texas aid for sheltering and mass care.

The Department of Energy also issued an emergency order on Monday allowing Texas power plants to produce more electricity to help with the power outages, Bloomberg reported.

The Washington Post's Capital Weather Gang reported that the storm and extreme cold across Texas and other parts of the south, including Oklahoma and Missouri, were caused by a disruption in the polar vortex in January.

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