A winter storm that brought heavy rain to the California coast this week is now wreaking havoc on much of the West, striking Denver with heavy snow and threatening parts of Texas with tornadoes.
The National Weather Service says the major winter storm has blizzard conditions for parts of Colorado and Wyoming, thunderstorms for the Southern and Central Plains, and tornado warnings for the Texas Panhandle.
For parts of Colorado and Wyoming, "the storm should reach peak intensity on Sunday, bringing snowfall amounts of possibly 4 feet for the highest elevations," the Weather Service said in a forecast discussion.
Nearly 2,000 weekend flights at Denver International Airport have been canceled, spokesperson Emily Williams said.
Colorado Gov. Jared Polis has declared a state of emergency and authorized deployment of National Guard troops "to provide search, rescue, and shelter assistance during the upcoming storm," according to a statement from his office Saturday.
In Texas, the cold, upper-level low is crashing into warmer air, creating the possibility of tornadoes, forecasters said.
"It does have to do a lot with the cold air in the North battling with the warm air in the south," Weather Service meteorologist Trenton Hoffeditz said.
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The Weather Service said a tornado watch was in effect for parts of New Mexico until 5 p.m. local time. Winds could reach speeds of 70 miles per hour, it said.
Hoffeditz, based in the Weather Service's Amarillo office, warned people in the region to "pay attention to television, radio, Twitter."
The Weather Service said the weather would move to the Mississippi Valley, the Midwest, the Southeast and the Mid-Atlantic by Monday.