The low temperature at BWI on Wednesday morning was 32 degrees. It was the first time the airport has touched the freezing mark since April 13, when the low was 29 degrees. This first freeze was relatively late for Baltimore. The average is Oct. 28 for BWI (Nov. 13 for downtown). During the past six years, the first-freeze dates for BWI have ranged from Oct. 13 (2006) to Nov. 9 (2004).