Pat Shingleton for Dec. 12, 2012

On this date in 2008, a few “piles” of snow lingered in south Louisiana. On Dec. 11, 2008, snowfall depths ranged from 3 to 8 inches in the Baton Rouge area. Since then, additional episodes have occurred, and as noted in a previous column, the stages of snow begin eight miles above the earth where water vapor condenses and becomes liquid. As the droplets grow, ice crystals form around tiny particles floating in the atmosphere. In the third stage, snow crystals take on a six-sided molecular structure, and depending upon the atmospheric temperature, they become different forms, such as plates, needles, dendrites and hollow columns. Additional water vapor condenses onto the crystals and they enlarge. Increased weight causes the crystals to fall into warmer air, forming larger flakes. Fastcast: Cold

ADDITIONAL WEATHER INFORMATION:

TODAY: Sunshine Returns (Sunny Icon) (57/32)

THURSDAY: Patchy Frost? (Sunny Icon) (62/39)

FRIDAY: Evening Rain (Cloudy Icon) 67/52

SATURDAY: Showery (Scattered Showers Icon) 71/49

SUNDAY: Clearing (Sunny Icon) 68/42

MONDAY: Breezy (Sunny Icon) 65/39