Tropical Atlantic Hurricanes, Easterly Waves, and West African Mesoscale Convective Systems

Figure 7

Daily pattern of the 700 hPa unfiltered relative vorticity for the Ivan (left) Maria (right) events, from the day when the long-lived MCS is initiated until the day the easterly wave left the West African coast. Only positive values larger than 0.5×10⁻⁵s⁻¹ are plotted. The contour increment is 0.5×10⁻⁵s⁻¹. The MCS initiation coordinates are marked as triangles.

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