What is a warm air mass where that is cut off from the ground?

A warm air mass that is cut off from the ground is known as a "warm occlusion." This occurs when a cold front overtakes a warm front, lifting the warm air above the cooler air masses below. Typically associated with mid-latitude cyclones, warm occlusions can lead to cloud formation and precipitation as the warm air cools and condenses. The result is often a layer of clouds and potentially significant weather changes in the affected area.