The major snowstorm that is headed to the eastern Great Lakes and Northeast has commenced across the southern Plains, creating a white Christmas and nightmares for travelers.

Snow earlier this morning led to a chain-reaction accident on Interstate 40 westbound in Del City, Okla. CNN reports the accident, which took place at 2:50 a.m. CST, involved 21 vehicles. Three of those vehicles were semi-trucks.

An unknown number of people were taken to the hospital with non-life-threatening injuries.

Snow will continue to increase and intensify as it spreads eastward across Oklahoma and northern Texas to western Arkansas, bringing rare Christmas snow to Oklahoma City and Dallas.

The snow will reach Little Rock tonight as a blizzard unfolds to the north across southeastern Missouri and southern Illinois. On Wednesday, the snowstorm will take aim at the eastern Great Lakes and Northeast.

A more detailed overview of the snowstorm's track can be found in this news story. Read below for more real-time updates on this Christmas snowstorm.

UPDATES:

7:23 a.m. CST: An inch of snow has fallen in Skellytown, Texas.

7:19 a.m. CST: Four inches of snow has already been reported near Glenrio, Texas. Gusty winds have dropped visibility down to near zero.

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5:00 a.m. CST: Freezing drizzle continues in Oklahoma City, Okla.

2:50 a.m. CST: An accident involving 21 vehicles, including three semi-trucks, has closed Interstate 40 near Del City, Okla.

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