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There are four different modes available for the parcel start conditions:
Surface
The parcel ascends from the surface, i.e. the lowest point of the profile. The format is as follows:
(mode: 'surface')
Custom
The parcel ascends from a given temperature, dewpoint and pressure. The format is as follows:
(mode: 'custom', start_t: start_temperature, start_td: start_dewpoint, start_p: start_pressure)
Mean layer
The parcel ascends from the mean temperature, dew point and pressure of a given pressure layer. The format is as follows:
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Please note that when bottom_p is omitted the layer starts at the surface.
Most unstable
The parcel ascends from the most unstable condition. To determine this, a parcel is started from all the points along the profile in the specified pressure layer. The start level of the parcel that results in the highest CAPE value will define the most unstable start condition. The format is as follows:
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