...DENSE FOG ADVISORY NOW IN EFFECT UNTIL 9 AM CDT THIS MORNING... ...FROST ADVISORY REMAINS IN EFFECT FROM 3 AM TO 8 AM CDT SUNDAY... The National Weather Service in Tulsa has issued a Dense Fog Advisory, which is in effect until 9 AM CDT this morning. * VISIBILITY...Quarter of a mile. * TEMPERATURE...Temperatures will fall into the lower to mid 30s by Sunday morning. * Impacts...Sudden reduction in visibility over short distances possible.