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Diane wonders why it seems you wake up some mornings to clear skies and bright sunshine, but by the afternoon, skies become cloudy and dismal. This occurs most often during spring but can happen in fall as well. One of the main causes is a large, cold pocket of air high above the surface associated with a large upper-level trough or cutoff low. Early morning sunshine warms the surface and the air above it, causing pockets of air to become warmer than the surrounding air. As a result, these warmed air pockets rise and cool but due to the colder temperatures of the surrounding environment caused by the cold air mass aloft, the pockets of air remain warmer than the surrounding air and continue to rise rapidly. The rising air eventually cools enough so that condensation takes over and clouds begin to form. This process leads to a sunny morning turning into a dismal afternoon. In many cases, skies will clear during the evening and overnight hours and start the whole process over again for the next day.

Anyone with a question for NewsChannel 8 meteorologist Neil Kastor can e-mail him at neil.kastor@wqad.com.