WVTS31 DTTA 261723 DTTC SIGMET 01 VALID 261720/262120 DTTA- DTTC TUNIS FIR VA CLD OBS AT 1700Z SFC/FL150 N3750 E01450- N3735 E01430- N3725 E01455- N3750 E01515-N3750 E01450=