Check out the view from space! Notice the cloud deck that has developed this afternoon which is in the same vicinity of a cold pool aloft.
You are probably wonder what a steep lapse rate means? It means a rapid decrease in temperature with height which is an indication of instability. Cold air above warm air is an unstable atmosphere and that means cloud development for us and showers in Tennessee.
How do we forecast a steep lapse rate? We look at forecast soundings of the atmosphere. Look at the image below and notice the blue line which is the temperature line and how it has a sharp angle with height. At the surface the temperature is much warmer than the air above which shows it quickly cooling. The image is a forecast sounding for 1pm today.
Jill Gilardi Fox 6 Meteorologist