Several indices and parameters are derived directly from [[Skew-T Log-P Diagrams]] ## Indices ### Thermal Index (TI) $ TI = T_e - T_p $ - where Te is the environmental temperature, Tp is the temperature of a parcel that has cooled at the DALR, **at a given level** - A derivation of expected temperature differential and thermal buoyancy - Lower values indicate greater buoyancy; <= -2 is considered the highest value for useable thermals in otherwise good conditions ### Lifted Index (LI) $ LI = T_e - T_p $ - where Te is the environmental temperature, Tp is the parcel temperature, **at the 500mb level** - Index of thunderstorm **severity**; lower values indicate greater severe thunderstorm potential ### K Index (K) $ K = (T850 - T500) + Td850 - (T700 - Td700) $ - where T is the temperature, Td is the dewpoint temperature, and the numbers indicate the level in mb - Index of thunderstorm **probability**; higher values indicate higher probability ## CAPE/CIN CAPE and CIN are parameters used to assess the enhancement and suppression (respectively) of convection in the atmosphere. ![[CAPE CIN.png]] ### Convective Available Potential Energy (CAPE) - "Positive area" (integral) between LFC and EL - Higher values indicate greater instability ### Convective Inhibition (CIN/CINH) - "Negative area" (integral) below LFC - Higher values indicate greater inhibition ## Quick Reference ![[skew T derivations.png]] ## Resources https://www.weather.gov/source/zhu/ZHU_Training_Page/convective_parameters/skewt/skewtinfo.html