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Dangerous snow, cold temperatures, trail twisters and floods in central US

Tornadoes, blizzards and heavy rain assaulted much of the country's middle section over the weekend, killing more than 20 people in three states, triggering emergency declarations in two and snarling airport traffic in Texas and beyond.

And it's not over yet.

@LukeMarkey tweeted 'This tornado was just east of us ... #Lucky' during the storms that hit Dallas.
@LukeMarkey | Twitter
@LukeMarkey tweeted 'This tornado was just east of us ... #Lucky' during the storms that hit Dallas.

Oklahoma was still bracing for as much as a foot of snow in the western part of the state on Monday, two to four inches of sleet in the middle and as much as 10 inches of rain in the east, where state emergency officials said they were anticipating the possibility of "major" flooding.

On Sunday afternoon, transportation officials had closed dozens of flooded roads in one section of the state, while in another they were racing to treat highways and bridges with salt and sand. As of 10:10 p.m. ET, there were nearly 54,500 power outages across the state, and officials were warning of what was to follow the snow and rain: "bitterly" cold temperatures beginning Tuesday.

In Missouri, where Gov. Jay Nixon said there had been eight flood-related fatalities and where he declared a state of emergency, residents were told to expect the same patchwork of potentially devastating weather: flooding and heavy rain were anticipated in the central and southern sections of the state, while in the north they could expect snow and freezing rain.

"I urge Missourians in flood-affected areas to stay alert, avoid travel if possible and never drive into a flooded roadway," Nixon said in a statement.

In the Dallas area of north Texas, where 11 people were killed after twisters ravaged the area on Saturday, up to 6 inches of rain was expected to hamper emergency crews late into Sunday night. With the ground already saturated, flash-flood watches remained in effect, the National Weather Service said.

Travelers in Texas airports were met with widespread delays and cancellations. Almost 1,350 departures and arrivals were canceled Sunday — 778 of them at Dallas-Fort Worth International alone. Around 1,650 more were delayed.

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In the western and northern sections of the state, blizzard warnings were in effect until Monday afternoon and whiteout conditions were expected from heavy snow blown by winds gusting to 65 mph, forecasters said. The combination of rain-filled clouds and plummeting temperatures meant a "life-threatening and crippling blizzard" was headed toward the Texas panhandle, the National Weather Service said.

Snow accumulations of 5 to 13 inches—with drifts to 10 feet—were likely in some areas of west and north Texas, southeast New Mexico and the Oklahoma panhandle.

Lubbock, Texas, Mayor Glen Robertson declared a state of disaster, because police, fire and EMS response times were expected to be hampered.

In New Mexico, Gov. Susana Martinez also declared a state of emergency Sunday, saying 16 inches of snow had already fallen in some parts of the state, making roads impassable. "This is a dire situation, especially in the eastern half of the state where the storm has hit hardest and continues to dump snow, Martinez said.

Later in the week, as the system moves northeast, it will also likely spread snow and ice through the Midwest and into New England. Snow will develop Monday night across much of New England and parts of northern and eastern New York, forecasters said.

Boston could see some accumulation Monday night — and while the snow should remain northwest of New York City, Sunday's expected record high temperatures in the 60s will turn into a wintry mix of sleet and freezing rain within about 24 hours.

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