Skew-T Thermodynamic Diagram Help

iln_sounding

Description of Terms

  • TP = Tropopause Height (mb)
  • MW = Height of maximum wind level (mb)
  • FRZ = Lowest freezing level (mb) or BG if below ground
  • WB0 = Height of Wet Bulb zero (mb) or BG if below ground
  • PW = Precipitable Water (in)
  • RH = Mean relative humidity (%) from the surface to 500 mb
  • MAXT = Est. maximum temperature (C) using a 150 mb layer
  • TH = 1000-500 mb thickness (m)
  • L57 = 700-500 mb lapse rate (C/km)
  • LCL = Lifting condensation level (mb)
  • LI = Lifted Index (C) using 100 mean layer above surface
  • SI = Showalter Index (C)
  • TT = Total Totals Index
  • KI = K Index
  • SW = Sweat Index
  • EI = Energy Index

Parcel Derived Quantities (yellow line on soundings)

Wind Parameters

  • STM = Estimated storm motion (kts) from 0-6000m AG mean layer, spd 75% of mean, direction 30 degrees veer from mean
  • HEL = Storm relative helicity 0-3000m AG (total value)
  • SHR+ = Positive shear magnitude 0-3000m AG (sum of veering shear values)
  • EHI = Energy helicity index (proportional to positive helicity * CAPE)
  • BRN = Bulk Richardson number 500-6000m AG (proportional to CAPE/ bulk shear)
  • BSHR = Bulk shear value (magnitude of shear over layer)

Source: The Ohio State University Atmospheric Sciences Program