Winter weather this week has closed schools and some businesses, and in turn cancelled a number of blood drives in the Louisville area.Red Cross spokesperson Karen Stecher says it happens almost every year.“When we see winter weather come through, folks are worried about safety, they aren’t out on the roads, they’ll have schools, business, churches that have to shut down for safety reasons, staff can’t make it in, and when that happens, blood drives end up being cancelled," says Stecher.Fourteen blood drives have been cancelled this week, resulting in 500 fewer pints of blood being collected.Stecher says for now the area’s hospitals have a sufficient blood supply, but donations are needed quickly to maintain that.