The region was under a dense fog advisory until 10 a.m. The fog was accompanied by a thin mist and low clouds, which eased throughout Thursday morning.

Still life in fog. Birds are grounded as heavy fog shrouds the down town Clearwater city marina below the Memorial Causeway bridge Thursday morning 1/11/2018. JIM DAMASKE | Times
Still life in fog. Birds are grounded as heavy fog shrouds the down town Clearwater city marina below the Memorial Causeway bridge Thursday morning 1/11/2018. JIM DAMASKE | Times
Sisters Grace Hill, 5, left, and Faith Hill, 4, of Palm Harbor, search for crabs amidst a thick fog which had rolled in over the Dunedin Causeway on Thursday (1/11/18) afternoon. The fog shrouded a mix of sun and clouds which held the highs in the mid to upper 70s. Forecasters expect a cold front to make its way into the state on Friday bringing a chance of late thunderstorm, followed by windy, cooler air into the weekend. DOUGLAS R. CLIFFORD | Times
Sisters Grace Hill, 5, left, and Faith Hill, 4, of Palm Harbor, search for crabs amidst a thick fog which had rolled in over the Dunedin Causeway on Thursday (1/11/18) afternoon. The fog shrouded a mix of sun and clouds which held the highs in the mid to upper 70s. Forecasters expect a cold front to make its way into the state on Friday bringing a chance of late thunderstorm, followed by windy, cooler air into the weekend. DOUGLAS R. CLIFFORD | Times
An osprey recovers a trout off the Dunedin Causeway as a thick fog rolls into the area on Thursday (1/11/18) afternoon. The fog shrouded a mix of sun and clouds which held the highs in the mid to upper 70s. Forecasters expect a cold front to make its way into the state on Friday bringing a chance of late thunderstorm, followed by windy, cooler air into the weekend. DOUGLAS R. CLIFFORD | Times
An osprey recovers a trout off the Dunedin Causeway as a thick fog rolls into the area on Thursday (1/11/18) afternoon. The fog shrouded a mix of sun and clouds which held the highs in the mid to upper 70s. Forecasters expect a cold front to make its way into the state on Friday bringing a chance of late thunderstorm, followed by windy, cooler air into the weekend. DOUGLAS R. CLIFFORD | Times
Dense fog shrouds the Ovation condominium tower, back, in downtown St. Petersburg, Thursday, 1/11/18 along 2nd Ave. NE. SCOTT KEELER | Times
Dense fog shrouds the Ovation condominium tower, back, in downtown St. Petersburg, Thursday, 1/11/18 along 2nd Ave. NE. SCOTT KEELER | Times
Dense fog shrouds the intersection of 2nd Ave. NE and Bayshore Drive in downtown St. Petersburg, Thursday, 1/11/18. The view is looking east toward the pier approach and Tampa Bay. SCOTT KEELER | Times
Dense fog shrouds the intersection of 2nd Ave. NE and Bayshore Drive in downtown St. Petersburg, Thursday, 1/11/18. The view is looking east toward the pier approach and Tampa Bay. SCOTT KEELER | Times