High Thursday for STL 86-John Fuller’s Forecast for Metro St. Louis:  Tonight:  Fair, Low 66.  Friday:  Partly sunny, 20% chance for an afternoon shower or t-shower.  Sun Index 8, Wind ESE 5, High 87, Low 65.  Saturday:  Partly cloudy, 20% chance for a shower, High 86, Low 67.  Sunday:  Mostly Sunny, High 87, Low 66.