Lift or Lack of Moisture...Which will win out?
Posted April 26, 2005
When we talk about our atmosphere we refer to rising air or sinking air. With rising air we tend to see clouds develop and if conditions are appropriate and there is sufficient rising motion or as we refer to in a shorthand sense lift, we would see rain develop. If we have sinking air or the air is moving in a downward direction we tend to see in certain conditions, the air warm and dry out which would make it hard for clouds to develop and so forth rain to develop.
With that being said we turn to back to Wednesday afternoon. Behind our cold front we will see the air dry out dramatically. In most instances this would not be conducive for any rain to develop. However we have a cold pocket of air aloft moving into the region in the afternoon. With the cold air aloft and warmer air at the surface, there will be a great change in temperature with height. This increases the instability in the atmosphere and increases the rising motion... Increasing the lift in the atmosphere. So which will win out...The drier air or intense rising motion? Will the air be too dry for any isolated showers to develop or will the rising motion be so strong that even limited moisture will be sufficient to conjure up a shower?. We will be watching the Live Doppler 5000 just like you will.
By the way, this would more likely happen from the Triangle area eastward to the coast late in the afternoon.