Portable BBQs should be moved into a shed or garage. Do not keep the tank in the shed or garage. Take the tank off the grill and place it outside next to the house.
After the storm, do not use the grill in the house or garage, only follow the manufacturer's instructions
If you live in an evacuation zone and you are leaving, turn off your tank by turning the service valve clockwise.
A picture of a service valve is shown.
When you return, call the gas company to check the regulator, appliances and piping for water damage.