Like mentioned. You should take special perils for convulsion of nature with your local insurer here, then MUST add another additonal cover to the kingdom of Thailand for your travelling period.

For Thai side insurance, you must buy the compulsory cover like usual, but do add the voluntary cover to protect you against third party claims like damage to houses, street post signs, barriers etc, vehicles.
But then again, customers rarely listens. They only panic when faced with the above situation. Some don't even to purchase insurance through agents like us anymore. Prefer to go buy online to save on the little bit of commision. So they dont get interaction and advise from agents regarding these situation.