Review a documented sounding, analyze observed layers and winds, and integrate supplied parcel virtual temperatures on explicit bounds.
Obtain a complete profile from an authoritative archive or documented model extraction. Record station or grid location, launch/valid time, pressure units, height datum and quality flags. Radiosonde measurements ascend over time and drift horizontally; a profile is not an instantaneous vertical photograph over the launch point.
Enter pressure, height and temperature in bottom-to-top order. Pressure must decrease and height must increase; investigate reversals, duplicates and unit errors before analysis. Keep missing dew point and wind values missing. Inspect inversion layers and zero-degree crossings only inside the sampled profile, without extrapolating beyond its top.
Use measured level heights where available. If studying the hydrostatic relationship, provide the log-pressure-layer mean virtual temperature rather than assuming the surface temperature represents the layer. Compare endpoint winds as vectors on one directional reference, keeping calm directions undefined.
Choose the parcel origin deliberately: surface, mixed layer and most unstable parcels can give different results. Use a documented sounding package to calculate the parcel ascent, LCL and humidity/virtual-temperature correction. Retain the environment and parcel virtual temperatures at compatible pressures and the method used to choose LFC and EL. Do not fabricate a parcel profile from a generic wet-bulb or Celsius converter.
Enter the actual virtual-temperature profile and its supplied LFC/EL bounds. Review the raw net integral and positive/negative-area breakdown. If the equilibrium level is above the data, select profile-top truncation explicitly and retain that limitation. A supplied 500 hPa parcel temperature can support a lifted index, but it remains a one-level diagnostic.
Repeat only meaningful alternate parcel or level-resolution cases while keeping the original profile. Compare with the trusted sounding package on identical data, moisture assumptions, constants and crossing selections. Record what changed and what remains unresolved. Interpret convection with the wider weather situation and qualified analysis rather than a universal CAPE, CIN or lapse-rate threshold.
Calculate observed layer lapse rates, interpolated freezing crossings and potential temperatures. · Calculate endpoint bulk vector shear from compatible observed wind levels. · Retain the observed environmental layer analysis alongside the parcel calculation.
Calculate hypsometric thickness from actual pressures and a documented mean virtual temperature.
Integrate supplied virtual-temperature differences in log pressure with visible CIN/CAPE bounds and truncation. · Save separate parcel/bound cases with source notes and inspect their raw integrals.
Subtract actual environment and parcel temperatures at 500 hPa without a severity lookup.
Loading your checklist…
CAPE usefulness depends on a documented parcel choice and virtual-temperature treatment.
MetPy documents supplied parcel profiles, virtual-temperature integration, logarithmic crossing treatment and selectable LFC/EL methods.
Different parcel origins or equilibrium-level choices explain many apparent disagreements between sounding products.
Net energy and separately signed areas answer different questions when a profile crosses buoyancy zero more than once.