Corona - A corona is a series of alternating dark and bright rings of light that can at times be seen surrounding the moon or sun. When a thin stratus cloud is present, a corona can be seen around the moon as the moonlight is diffracted by the water droplets in the cloud. The corona of the sun is most visible during a total solar eclipse.

Nacreous Clouds - Nacreous clouds are rare and are rarely found too far south of the poles. They form at an impressive elevation between 68,000 to 100,000 ft where temperatures are at or below -108F. They appear as large thin discs which tend to reflect vivid colors. Due to their high elevations, they can only be seen when the sun is just below the horizon.

Texas Hooker - A low pressure system that originates in the Panhandle of Texas and initially moves eastward, but then hooks to the northeast towards the Upper Midwest and Great Lakes region. When this type of low pressure system develops in the winter season heavy snow can be expected on the north and west sides of the low. The biggest snows of the season for the Northern Plains can generally be traced back to a Texas hook low.

Deposition - The process where water turns directly from vapor to ice, without first becoming liquid. A common instance of deposition is when frost forms on the grass during cold mornings.

Frontolosis - The dissipation of a frontal zone due to a weakening contrast between two air masses. The temperature gradient weakens during frontolysis, meaning the rate of change of the temperature along the frontal boundary is lessening. At the end of frontolysis, the front no longer exists. The opposite of frontolysis is frontogenesis.

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!

Pluie - This is the french word for rain. To say, "it is raining today" one would say, "Il pleut aujourd'hui."