Slide 16 of 29
Notes:
Vertical cross section of winds (barbs/KT), convergence (red) and divergence (blue).
Although an area of low level convergence extends across this axis, an area of deeper convergence is evident to the east of this trough. This area of deeper low level convergence is bounded by 18N 37W and 18N 40W, and extends up to approximately 600 hPa. Immediately above this area, note the area of upper divergence as denoted by the blue contours.
West of the trough, between 400-600 hPa, note the area of mid level convergence bounded by 18N 42W and 18N 49W. An area of low level divergence is clearly evident just below the area of mid level convergence.
This conforms quite well with the ideal model of a positively tilted tropical wave.