ATLANTA -- A wintry mix of snow, sleet and freezing rain continued falling Thursday morning in the counties north of Atlanta.

The threat of slick roads convinced some school officials to cancel classes on Thursday. Metro Atlanta school systems canceling classes included: Carroll County, Cherokee County, Forsyth County and Hall County.

Other systems around the state closed for the day include: Banks County Schools, Dawson County Schools, Fannin County Schools, Franklin County Schools, Gilmer County Schools, Habersham County Schools (12-month staff report), Haralson County Schools, Hart County Schools, Lumpkin County Schools, Pickens County Schools, Rabun County Schools, Stephens County Schools, Towns County Schools, Union County Schools and White County Schools.

Click here for a full list of closed schools.

Delta Air Lines canceled about 70 flights at Hartsfield-Jackson Atlanta International Airport early Thursday, Delta spokeswoman Susan Elliott said. Elliott suggested that passengers check the status of their flight on Delta's Web site before heading to the airport.

AirTran canceled 12 flights at the Atlanta airport, said spokesman Tad Hutcheson, who added that more cancellations were possible later in the day at airports further north as the storm moved up the East Coast.

Sleet and snow started falling first in central Georgia as moisture from the Gulf of Mexico collided with a blast of cold air from the northeast. It moved north gradually, hitting metro Atlanta in late afternoon and threatening to dump 2 to 4 inches of snow in northeast Georgia, according to WSB-TV Channel 2 chief meteorologist Glenn Burns.

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Estimates of overnight snowfall included: Lumpkin and White counties, 2.5 to 3 inches, Gilmer County, a half inch to 1.5 inches; Banks County 1.5 inches, and Forsyth County, half an inch to 1 inch.

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A similar system -- though weaker -- may bring rain to the state tomorrow night and Saturday morning.

Rain should end during the day with temperatures continuing to climb to the upper 30s in the northeast Georgia moutains, according to WSB-TV Channel 2 meteorologist Karen Minton. The rest of north Georgia should see temperatures from the upper 30s to lower 40s.

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