Surface Lifted Index

Surface Lifted Index.

Surface Lifted Index

This is a computer forecast of the stability of the atmosphere for today at 1 PM EST. There is a greater potential for thunderstorms or heavy showers when it is unstable and sufficient moisture is available. Areas that are unstable are shown in shades of yellow and red. Yellow areas are marginally unstable. The brighest red areas are very unstable. Blue areas are very stable.