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This generates a plot with a map of MSLP, a red line and underneath a cross-section plot along that red-line.

The default plot shows potential vorticity (PV) and potential temperature roughly through the centre of the Hurricane and the cut-off low.

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Cross-section data is only available every 24hrs, not every 3 hrs for the horizontal maps.

This means the 'steps' value in the macro macros is only valid for the times:  [2012-09-20 00:00], [2012-09-21 00:00], [2012-09-22 00:00], [2012-09-23 00:00], [2012-09-24 00:00], [2012-09-25 00:00]

Changing fields

Note that a A smaller set of fields is available for cross-sections: temperature (t), potential temperature (pt), relative humidity (r), potential vorticity (pv), vertical velocity (w), wind-speed (speed; sqrt(u*u+v*v))

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#Cross section line [ South, West, North, East ]
line = [30,-29,45,-15]

The red line indicating the cross-section location (red line) can be changed in this macro by defining the end points of the line as shown above.

Remember that if the forecast time is changed, the storm centres will move and the cross-section line will need to be repositioned to follow specific features. This is not computed automatically, but must be changed by altering the coordinates above.

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