8 Cool Things to Look For During Winter

1. Snow Rollers

In the wake of fresh snow that fell in northern Illinois on Dec. 4, snow rollers formed in Dekalb County at the campus of Northern Illinois University.
This winter phenomenon occurs when strong winds pick up moist snow and blow it along the ground, eventually building a cylinder of snow that is often hollow in the middle. When the snow roller grows too large for the wind to propel it farther, it stops
Here are the optimal conditions for snow roller generation, according to the National Weather Service:

• Existing icy or crusty snow cover, so additional snow will not stick to it.
• Additional wet, loose snow on top of the icy, crusty snow cover
• Wind strong enough to scoop out balls of snow and propel snow roller foward.
• At least some slope to the ground.

  2. Snowdrifts

  One of the things that "wows" the eyes of meteorologists during winter storms are snowdrifts.
  High winds in combination with snow on the ground or falling snow can pile up high against structures likes homes.
  

  3. Hot Water Freezing in Midair

  An experiment we see sometimes during frigid arctic air outbreaks is tossing hot water into the air. The National Weather Service in Fairbanks, Alaska, did this on Dec. 4, 2016 when temperatures there were in the minus 30s.
  Once airborne, the water droplets freeze instantly into tiny ice crystals before evaporating in the dry air mass. It works best when the air is very dry in subzero temperatures.
  

   

  4. Frost Flowers

  Frost flowers are a fairly rare thing to spot.
  They develop where there is moist, unfrozen soil during below-freezing temperatures (32 degrees or lower).
  Water pulled up from the soil into a plant's stem freezes, expands and splits the stem. As more water is drawn up through the stem split, more freezing occurs, eventually forming a fragile petal of the frost flower.
  These amazing formations can melt or sublimate (transition from ice to water vapor) quickly after sunrise.
  
  

  5. Hoarfrost

  Frost is not an uncommon sight during the cold months of the year, but hoarfrost is in a league of its own.
  One or more days in a row of freezing fog (fog with air temperatures of 32 degrees or colder) is a perfect scenario for the formation of hoarfrost. This is because there is more moisture in the air compared to a day that might produce a typical frost.
  With the extra moisture in the air, the interlocking crystal patterns of frost become more intricate and much larger, building up to a greater depth on tree branches, signs, fences, anything.

  6. Pancake Ice

  Resembling frozen lily pads, pancake ice forms when there is some wave action on a body of water and temperatures are just below freezing.
  Pancake ice can begin as a thin ice layer (known as grease ice) or slush on the water surface, which accumulates into quasi-circular disks. The "lily pad," or raised-edge appearance of pancake ice, can form when each disk bumps up against one another, or when slush splashes onto and then freezes on the slab's edge.
  The floating disks of ice can be up to 10 feet in diameter and four inches thick.
  

  7. Thundersnow

  For many meteorologists and weather enthusiasts, hearing the crack of thunder during a snowstorm triggers excitement.
  When thundersnow occurs, snowfall rates tend to be very heavy, many times reaching an inch or more per hour.
  A pocket of unstable air aloft is needed to generate this fairly rare weather phenomenon.
  Typically, these pockets of instability develop as upward bumps on top of the flat layer of snow clouds already in place. This development occurs in response to strong lifting from an upper-level disturbance in the atmosphere.
  If temperatures are between 14 degrees and -4 degrees inside the upward bump where the elevated pocket of unstable air resides, snowflakes and small hailstones can form. As the snowflakes and hail collide, electrical charges will build up, making lightning and thunder possible.
  

  8. Snow Crystals

  If snowflakes stay separated from each other, and if you look closely enough, you can sometimes see the structure of snowflakes with your naked eye.
  There are many different types of crystal patterns, and these star-shaped snowflakes above are just one example. The dendrite, a star-shape with varying patterns, is the most common shape of a snowflake.
  The type of snow crystals you may observe depends on the temperature and humidity, according to snowcrystals.com.