And Jesus answered and said to them: “Take heed that no one deceives you. For many will come in My name, saying, ‘I am the Christ,’ and will deceive many. And you will hear of wars and rumors of wars. See that you are not troubled; for all these things must come to pass, but the end is not yet. For nation will rise against nation, and kingdom against kingdom. And there will be famines, pestilences, and earthquakes in various places. All these are the beginning of sorrows. -Matthew 24:4
It’s not just the smiling megachurch prosperity preachers you need to look out for. The false doomsday prophets make a good living for themselves by selling books, speaking engagements, gold and survival supplies too. The false doomsday prophets are like the boy that cried wolf, troubling true saints and numbing them to the call of true prophets.
Many of these men release a ‘prophetic word’ when the stock market takes a big hit but then are totally silent when it inevitably rebounds. They are nothing more than speculative economic theorists trying to produce spiritual results through fleshy means. In this they both fail as economists and as prophets. Others are extreme zionists who support Christians going to war to kill arabs for the sake of nation state Israel. Feeding constant fear to the saints is a cloak for misleading them into supporting war and violence. Saints of God would do well to avoid both types of false doomsday prophets while still being aware that troubling times are ahead.
Lastly, many of these men use the name of Jesus and scripture loosely but only to serve their own end. They ultimately want to steer you to their bank accounts, nation states, political party, etc as opposed to pure devotion to Jesus Christ. Look at the emphasis of Peter while prophesying the future destruction of the earth (I believe it to be referencing the temporal destruction of Jerusalem in 70ad as well). 
Therefore, since all these things will be dissolved, what manner of persons ought you to be in holy conduct and godliness -2 Peter 3:11