Altostratus Clouds - Are gray or blue-gray middle level clouds composed of ice crystals and water droplets. These clouds usually cover the entire sky. In the thinner areas of the cloud, the sun may be dimly visible as a round disk.

Stratus - A low, generally gray cloud layer with a fairly uniform base. Stratus clouds have the appearance of fog that doesn't reach the ground. These clouds tend to be associated with either no precipitation or light precipitation such as drizzle.

Blizzard Warning - Blizzard Warnings are issued when visibilities are reduced to a quarter mile or less for 3 hours or longer. Wind speeds must also be sustained at 35 mph with frequent higher gusts in order to achieve blizzard conditions.

Geostrophic wind - A theoretical wind which results from the equilibrium between the horizontal components of the pressure gradient force and the coriolis force above the friction layer. Geostrophic winds blow parallel to isobars.

Updraft - A stream of air that accelerates upward from the surface. The strongest updrafts are found within thunderstorms. Strong thunderstorms can see updraft speeds of over 100 mph!

Perihelion - The point in the orbit of a planet in which it is closest to the sun. For Earth, the time of year when it's orbital path comes closest to the sun occurs in early January. This can be surprising to learn for folks in the Northern Hemisphere who experience winter during that time of the year. This just proves how much more impactful the Earth's tilt is compared to its distance from the sun during its orbit.

Stratosphere - The atmospheric shell above the troposphere and below the mesosphere. This layer of the atmosphere starts at around 8 miles above the surface and extends to around 30 miles above the earth. 19% of the atmospheric gases on earth are found here. The earth's ozone layer is located in this layer of the atmosphere.