This task is intended for VLA use only. Plots elements of the weather table; estimates opacity.

Generates opacity estimates from both the weather data and a seasonal model. By default the returned opacity is the mean of these predictions, but this can be adjusted with seasonal_weight. Please note that the opacity determined in this manner is only a rough estimate which could propagate to an error when bootstrapping the flux density.

These methods and models are described in detail in EVLA Memo 143, VLA Test Memo 232, VLA Scientific Memo 176, and references therein.

Saves the plot to the following default file:  MS name + .plotweather.png. Custom plot filenames must end in one of: .png, .pdf, .ps, .eps or .svg

If run as a function, will return the mean zenith opacity per spectral window.

The wind direction is defined as the direction where the wind is coming from (the arrow points into the wind), with north at the top and counterclockwise through west, south, and east.