2. Parameters

Stability Assessment » Lifted Index (LI) Skew-T Procedure

Skew-T procedure to determine lifted index (LI)
  1. Find the mean temperature (T) and dewpoint (Td) in the lowest 100 hPa.
  2. From those mean T and Td, located at the midpoint of the layer, find the LCL.
  3. From the LCL lift the parcel moist-adiabatically to 500 hPa and find the parcel temperature (T′).
  4. Given the 500 hPa sounding temperature (T500), LI is computed as follows:

LI = T500 - T′