WSCN07 CWAO 171302 CZQX SIGMET B4 VALID 171300/171700 CWUL- CZQX GANDER DOMESTIC FIR SEV ICE (FZRA) FCST WI 120NM WID LINE BTN N5436 W06820 - N5407 W05652 - N5100 W05000 SFC/FL040 MOV NNE 25KT NC=