By all means, ready thoroughly. And critically.
A hand-picked assemblage of quotes, excerpts, etc., describing a storm hitting New Orleans (made, as it happens, while a storm was heading toward New Orleans), pulled out of the files and bolstered with a divine one-year window of opportunity is certainly something that needs to be viewed critically.
False prophets always manage to get close to the truth. Sometimes they are even "accurate".
How could one avoid predicting a great storm harming NO? Even the weathermen have been predicting this one.
As for purification, I might point out that after a worst case flood, purification is going to take a while. Sewage treatment is below sea level.
My own prediction is that the worst case will not happen this time.