most_unstable_parcel

metpy.calc.most_unstable_parcel(pressure, temperature, dewpoint, height=None, bottom=None, depth=<Quantity(300, 'hectopascal')>)[source]

Determine the most unstable parcel in a layer.

Determines the most unstable parcel of air by calculating the equivalent potential temperature and finding its maximum in the specified layer.

Parameters
  • pressure (pint.Quantity) – Atmospheric pressure profile

  • temperature (pint.Quantity) – Atmospheric temperature profile

  • dewpoint (pint.Quantity) – Atmospheric dewpoint profile

  • height (pint.Quantity, optional) – Atmospheric height profile. Standard atmosphere assumed when None (the default).

  • bottom (pint.Quantity, optional) – Bottom of the layer to consider for the calculation in pressure or height. Defaults to using the bottom pressure or height.

  • depth (pint.Quantity, optional) – Depth of the layer to consider for the calculation in pressure or height. Defaults to 300 hPa.

Returns

  • pint.Quantity – Pressure, temperature, and dewpoint of most unstable parcel in the profile

  • integer – Index of the most unstable parcel in the given profile

See also

get_layer

Notes

Only functions on 1D profiles (not higher-dimension vertical cross sections or grids). Since this function returns scalar values when given a profile, this will return Pint Quantities even when given xarray DataArray profiles.

Changed in version 1.0: Renamed heights parameter to height