Today is the first day of school for Polk County students. With the kids returning to class today, the Polk School District is bracing for a wintery blast to blow in at the end of the week. The latest data from the National Weather Service indicates that the best chance of snow will occur Thursday afternoon after 1 p.m. and will continue throughout the afternoon and into the nighttime hours. The snow is expected to end overnight on Thursday, but temperatures may not get above freezing. Accumulations of up to an inch of snow are expected. Stay tuned to the Big Double A for the latest updates from the Weather Channel and the Polk School District.