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HCCT represents instantaneous values and as such the field itself could be quite noisy. It can happen that seemingly cloudless grid boxes where DMC has not been triggered (yet) are surrounded by very high and thick convective clouds produced by DMC (Fig.2). In such instances there will often be heavy precipitation underneath, but the model would be diagnosing this as large scale not convective . It is as if the convection is being completely resolvedat this moment.
Fig. 2. HCCT in a widespread area of DMC over Western Africa. Marked blank areas represent areas where DMC is not active surrounded by thick clouds where DMC is taking place.
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