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Have a look at the supplied Python script plot_max_value_locations.py and execute it. It shows one way to plot the locations of the highest values, by masking off the lower values as invalid. Another way would be a customised Contouring icon that only plotted large values.
Examine the GRIB metadata
Right-click on the GRIB file icon and choose Examine. This brings up the GRIB examiner tool - have a look!
Compute and plot a time series from a point
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