WSBC31 FBSK 160850 FBGR SIGMET A02 VALID 160850/161250 FBSK- FBGR GABORONE FIR FRQ TS OBS WI S2053 E02224 - S2056 E02456 - S2213 E02643 - S2417 E02521 -S2053 E02224 TOP FL460 MOV E NC=