WCCA31 MDSD 241600 SIGMET MDCS SIGMET A4 VALID 241600/242200 MDSD- MDCS SANTO DOMINGO FIR: TC ISSAC OBS N1618 W07048 AT 1600Z CB TOP FL530 WI 185NM OF CENTRE MOV WNW 12KTNC FCT 2100Z TC CENTRE N1702 W07200 OTLK TC CENTRE 250400 N1751 W07313=