.. _sphx_glr_examples_Advanced_Sounding.py:


=================
Advanced Sounding
=================

Plot a sounding using MetPy with more advanced features.

Beyond just plotting data, this uses calculations from `metpy.calc` to find the lifted
condensation level (LCL) and the profile of a surface-based parcel. The area between the
ambient profile and the parcel profile is colored as well.



.. code-block:: python


    from datetime import datetime

    import matplotlib.pyplot as plt

    import metpy.calc as mpcalc
    from metpy.io import get_upper_air_data
    from metpy.io.upperair import UseSampleData
    from metpy.plots import SkewT
    from metpy.units import concatenate








.. code-block:: python

    with UseSampleData():  # Only needed to use our local sample data
        # Download and parse the data
        dataset = get_upper_air_data(datetime(1999, 5, 4, 0), 'OUN')

    p = dataset.variables['pressure'][:]
    T = dataset.variables['temperature'][:]
    Td = dataset.variables['dewpoint'][:]
    u = dataset.variables['u_wind'][:]
    v = dataset.variables['v_wind'][:]







Create a new figure. The dimensions here give a good aspect ratio



.. code-block:: python

    fig = plt.figure(figsize=(9, 9))
    skew = SkewT(fig, rotation=45)

    # Plot the data using normal plotting functions, in this case using
    # log scaling in Y, as dictated by the typical meteorological plot
    skew.plot(p, T, 'r')
    skew.plot(p, Td, 'g')
    skew.plot_barbs(p, u, v)
    skew.ax.set_ylim(1000, 100)
    skew.ax.set_xlim(-40, 60)

    # Calculate LCL height and plot as black dot
    l = mpcalc.lcl(p[0], T[0], Td[0])
    lcl_temp = mpcalc.dry_lapse(concatenate((p[0], l)), T[0])[-1].to('degC')
    skew.plot(l, lcl_temp, 'ko', markerfacecolor='black')

    # Calculate full parcel profile and add to plot as black line
    prof = mpcalc.parcel_profile(p, T[0], Td[0]).to('degC')
    skew.plot(p, prof, 'k', linewidth=2)

    # Example of coloring area between profiles
    greater = T >= prof
    skew.ax.fill_betweenx(p, T, prof, where=greater, facecolor='blue', alpha=0.4)
    skew.ax.fill_betweenx(p, T, prof, where=~greater, facecolor='red', alpha=0.4)

    # An example of a slanted line at constant T -- in this case the 0
    # isotherm
    l = skew.ax.axvline(0, color='c', linestyle='--', linewidth=2)

    # Add the relevant special lines
    skew.plot_dry_adiabats()
    skew.plot_moist_adiabats()
    skew.plot_mixing_lines()

    # Show the plot
    plt.show()



.. image:: /examples/images/sphx_glr_Advanced_Sounding_001.png
    :align: center




**Total running time of the script:** ( 0 minutes  0.631 seconds)



.. container:: sphx-glr-footer


  .. container:: sphx-glr-download

     :download:`Download Python source code: Advanced_Sounding.py <Advanced_Sounding.py>`



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     :download:`Download Jupyter notebook: Advanced_Sounding.ipynb <Advanced_Sounding.ipynb>`

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