Moisture Advection
From what direction is the moisture over Zambia and Botswana being drawn? Review the data, then answer the question below.
Select the dominant direction from which the moisture over Zambia and Botswana is being being drawn. Then click Done.
The correct answer is E.
The wind converging into the low/trough at all levels comes from the northeast. This is significant because it's bringing a warm tropical air mass into the area, making moisture available in a deep layer from 850 hPa to 500 hPa at least.