First Alert Weather December 31, 2021 6:21 am NBC10 First Alert Weather: Dense Fog Friday Morning Visibility in some spots will be only about a mile as dense fog clouds the Philadelphia region Friday morning. NBC10 First Alert Meteorologist Steve Sosna has your full forecast. US & World Videos 2:44 Gray, warmer Monday 2:24 Gray Monday 2:00 Dreary Monday weather 3:01 Keep your umbrellas handy as rain will be on and off all week 2:35 Isolated showers continue Sunday night into the morning