What triggers tropical cyclogenesis off the West African coast?

Our analyses provide clues on the possible role of intra-seasonal (beyond 10 days) oscillation of the Indian summer monsoon in triggering tropical cyclogenesis off the West African coast via changing the North African summer monsoon. Enhanced convection over Northwest India and Pakistan can induce deep convection over North Africa and activate African Easterly waves after about 20 days, which can further trigger the cyclogenesis off the West African coast after an additional 20 days. Activation of deep intra-seasonal convection over North Africa is an important link in this lagged relationship. A potential for long-range prediction of tropical cyclogenesis off the West African coast may exist by monitoring the intra-seasonal convective variation over India and North Africa.