Page:CAB Accident Report, United Airlines Flight 21.pdf/34

 temperature of 31 degrees, with a wind from west northwest of 9 miles per hour, including a pilot report locating the top of the overcast at 5000 feet and light to moderate icing existing between 1000 and 5000 feet.

The 4:53 weather observation reported the ceiling at 1000 feet, an overcast sky, with scattered clouds at 600 feet, a visibility of one mile, with light snow, light fog and light smoke, a temperature of 33 degrees, a dewpoint temperature of 31 degrees. The 5:10 weather observation reported the ceiling at 600 feet, an overcast sky with lower broken clouds, a visibility of ¾ of a mile, with light snow, light fog and light smoke, a temperature of 32 degrees, dewpoint temperature of 31 degrees, and wind from the west northwest of 9 miles per hour. the 5:20 weather observation reported no change since the 5:10 report. The 5:31 weather observation reported the ceiling at 1200 feet, with an overcast sky and lower scattered clouds at 600 feet, a visibility of one mile, with light snow, light fog and light smoke, a temperature of 32 degrees, a dewpoint temperature of 31 degrees, with a wind from the north northwest of 9 miles per hour. The 5:35 weather observation reported no change since the 5:31 report. The 5:50 weather observation reported a ceiling of 900 feet with an overcast sky and lower scattered clouds at 600 feet, a visibility of one mile, with light snow, light fog and light smoke, a temperature of 32 degrees, a dewpoint temperature of 31 degrees, with a wind from the north northwest of 9 miles per hour.

According to the airport control tower log there were thirteen arrivals and eighteen departures of airlines flights of seven different airlines during the period between 3 o'clock and 8 o'clock of the afternoon of December 4.