tambreet just referred to a headline stating that Galveston residents who do not evacuate "may face certain death". He suggests alternatively that they will certainly face possible death. A diarist on dKos quotes a NWS definitions of coastal flooding impacts of "high impact" which says stay-behinds "will face certain death".
So the official word from the United States Government to residents of Galveston, TX and coastal communities within 150 miles in either direction is GTFO OR DIE.
And needless to say, POOL'S CLOSED