16 million in Plains States threatened by severe storms bringing wet snow, heavy rain

More than 16 million people were threatened by severe weather Sunday as heavy rainfall was expected to trigger flash floods in the Gulf of Mexico and the Plains and Colorado continued to deal with wet, heavy snow.

Parts of Colorado, northern New Mexico, Wyoming, western Nebraska and western South Dakota would see wet, heavy snow through Sunday night, according to Michael Palmer, a lead meteorologist with the Weather Channel. The slushy snow, paired with heavy winds could cause power outages and downed trees, Palmer said.

Related: Snow Socks Colorado, More Severe Weather Expected in Mid-Section of Country

Higher elevations in Colorado had already accumulated up to 3 feet of snow by Sunday morning, while Denver picked up between 8 and 12 inches, Palmer said. More than 800 flights out of Denver International Airport had been cancelled Sunday, where nearly a foot of snow was dropped, according to the National Weather Service.

More than 3 million people in the region remained under a winter storm warning Sunday, according to Weather.com.

Meanwhile, another 12 million people in the Plains were under flash flood warnings and watches or severe weather warnings tied to the possibility of severe storms, according to Weather.com. Palmer said a "copious" amount of rain would fall in the Plains, with the heaviest rain totally up to 8 inches in a stretch from Texas to western Nebraska.

Parts of Texas, Oklahoma, Kansas and Nebraska had already picked up double the amount of rainfall that was expected for all of April in just two days, according to Weather.com — and more rain could bring on flash flooding.

Texas and Oklahoma were also facing the threat of tornadoes and large hail along with the downpours, according to Weather.com

Texas Governor Greg Abbott announced Sunday that the Texas State Operations Center was on high alert.

"It is crucial that Texans stay clear of rising waters and heed warnings from state and local officials, who stand ready to assist and support communities impacted as this weather system passes through Texas," he said.

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