While Running in hole 3-1/2 EUE singles from cat walk - at 1871m (1992 TD), the weather changed and it started to rain followed by rapidly increasing severe winds. The crew followed the well securing procedures and started securing the well. After installing FOSV the weather had become too severe to safely continue and the NTP moved the crew to tea room. The storm worsened within 5 mins, this resulted in bringing the Hoist Mast down on to the Rig Manager Caravan, which also contains the tea room. All personnel reported, no injuries