metpy.calc.showalter_index(pressure, temperature, dewpoint)

Calculate Showalter Index.

Showalter Index derived from [Galway1956]: SI = T500 - Tp500

where: T500 is the measured temperature at 500 hPa Tp500 is the temperature of the parcel at 500 hPa when lifted from 850 hPa

  • pressure (pint.Quantity) – Atmospheric pressure, in order from highest to lowest pressure

  • temperature (pint.Quantity) – Ambient temperature corresponding to pressure

  • dewpoint (pint.Quantity) – Ambient dew point temperatures corresponding to pressure


pint.Quantity – Showalter index