AREAS OF FOG, LOCALLY DENSE AT TIMES, TO REDUCE VISIBILITY INTO THE MORNING... Surface weather observations across eastern Massachusetts and Rhode Island indicate areas of fog. Visibilities will be commonly in the one half to 1 mile range, though locally dense fog may develop at times. A Dense Fog Advisory may be needed if widespread dense fog develops. Improvement is likely to be slow. Motorists should be prepared for sudden changes in visibility. Use low beam headlights and keep a safe distance between your vehicle and the one ahead of you.