Some areas of fog have begun to develop early this morning. The fog will continue to develop and affect portions of Oklahoma and western North Texas through the early morning hours. Visibilities mainly range from 4 to 6 miles. However… in parts of western Oklahoma and western North Texas visibilities are lower and variable with some locations at one mile or less. These lower visibilities could develop in other areas of Oklahoma and western North Texas early this morning. Drivers need to be prepared for sudden reductions in visibilities. The fog is expected to dissipate by mid-morning.