Dry air began impacting Nadine on September 17, though outflow from the storm prevented significant weakening.[18] Despite a large flare of deep convection over the northern semicircle, Nadine weakened slightly later that day.[19] Further weakening occurred on the following day, after the burst in deep convection on September 17 deteriorated.[20] Later on September 18, most of the deep convection dissipated, with the strongest of the remaining shower and thunderstorm activity being located within a band located west and northwest of the center.[21]