Fig. (4a) Atmospheric (Skew- T) sounding at Barbados, WI, 1200 GMT, June 28, 2015, showing the elevated SAL (shaded) between 550 and 750 mb. Potential temperature, sloping blue lines toward the left, is nearly constant with height in the SAL with a potential temperature slightly higher that 40˚C; the 40˚C isentrope, is marked by an arrow and labeled accordingly. Mixing ratio (sloping dashed lines leaning toward the right) is nearly constant with height in the upper part of the SAL with a value of 3 gkg-¹.