9 p.m. Most school districts closedMost area school districts have called off school for Friday. They include Aledo, Arlington, Birdville, Burleson, Crowley, Dallas, Eagle Mountain-Saginaw, Fort Worth, Grand Prairie, Grapevine-Colleyville, Hurst-Euless-Bedford, Mansfield and White Settlement. 6:25 p.m. TCU cancellationsAll classes and activities at TCU were canceled for Friday.5 p.m. Democratic activist training on Saturday has been canceledDemocratic Activist Training scheduled from 9 a.m. to 3 p.m. Saturday at the UNT Health Science Center has been canceled. It will be rescheduled after the holidays.4:45 p.m. Jury duty canceledJurors do not need to report for Tarrant County trials on Friday. 4:40 p.m: Health science center and clinics closeUNT Health Science Center and all UNT Health clinics will remain closed all day Friday. 4:30 p.m. : Grapevine parade canceledGrapevine’s annual Parade of Lights on Main Street, scheduled for Thursday night, was canceled and will be rescheduled at a later date.3:36 p.m.: TCC classes canceledTCC canceled all Friday classes. A decision will be made about Friday evening classes and Saturday day classes by 3 p.m. Friday.3:05 p.m.: Christmas in the Stockyards postponedChristmas in the Stockyards, a holiday festival in the Fort Worth Stockyards, has been rescheduled from Saturday to Dec. 14. For more information go to www.stockyardsstation.com2:55 p.m.: Some exams postponedTexas A&M University School of Law closes at 5 p.m. Thursday. Evening exams postponed. Friday status pending.12:30 p.m.: Jingle Bell run still onPeople were still registering for Jingle Bell Run/Walk 2013 in Fort Worth on Thursday morning. The popular fundraiser, for the Arthritis Foundation, is planned for Saturday at Burnett Park in downtown Fort Worth. As of Thursday morning, about 3,000 people had registered. Organizers continued to monitor the weather before deciding how the cold blast would affect the event. Noon: Flights canceled at DFW Airport American Airlines and American Eagle have already canceled nearly 500 flights in and out of Dallas Fort Worth Airport through 11 a.m. Friday. American is allowing customers from DFW Airport to change travel plans if they are traveling from DFW Airport between Wednesday and Saturday. 11:45 a.m.: UNT closing at 1 p.m.The University of North Texas announced classes, offices and libraries will stay closed on Friday.11:30 a.m.: Closings up in the airCity of Fort Worth will decide at 6 a.m. Friday about what will be open and closed.Tarrant County Courthouse will be open Friday. 10:30 a.m. : U.S. Sen. Ted Cruz’s speech canceledFort Worth Chamber of Commerce officials have called off Friday's luncheon featuring Republican U.S. Sen. Ted Cruz. Cruz was scheduled to talk to a sold out Leaders in Government luncheon at the Petroleum Club.