The National Weather Service issued an updated weather alert at 6:39 a.m. on Monday for dense fog until 9 a.m. for Putnam and Westchester counties."Locally dense fog is currently being observed across portions of the Lower Hudson Valley, Southern CT and Eastern Long Island. These locally dense patch es of fog will reduce visibility to one quarter mile or less. Be prepared for rapidly changing visibilities. The fog is expected to dissipate with daytime warming by 9 a.m. If driving, slow down, use your low beam headlights or fog lamps, and leave plenty of distance ahead of you," according to the weather service. ...read more read less