Patchy dense fog has developed in the valley areas of southwest Iowa early this Tuesday morning including areas of Cass and Adair Counties south into Adams and Taylor County. Visibility has been reduced to one quarter mile or less at some locations.

If traveling early today over portions of southwest Iowa; especially prior to 8 AM CDT, be alert to rapidly changing visibility. Use extra caution while traveling through this region and allow extra time to reach your destination safely.

Use low beam headlights and allow extra distance between you and the vehicle ahead of you. Be extra careful at intersections due to the reduced visibility. The fog should begin to burn off after 7 am with conditions much improved by 8 AM CDT.