A mobile home can overturn very easily even if precautions have been take to tie down the unit. If there is no building nearby, lie flat in a low spot. Use your arms and hands to protect your head as tornadoes cause debris to be blown at very high speeds. Do not seek shelter under highway overpasses and bridges - weaker structures could be destroyed from the high winds and dangerous flying debris. You will be safer lying flat in a low-lying area where wind and debris can blow above you.
Tornadoes come from severe thunderstorms, which can produce a lot of rain.
If you see water rising, quickly or flood waters coming toward you, move to another spot.