the guy's name is camping, and according to wikipedia this is how he knows the world is ending tomorrow
Examples of how Camping's teachings vary from past conventional doctrines are:
Departing from doctrines stating no one can know the time of Christ's second coming, he teaches that the exact times of the Rapture and the End of the World are to be revealed sometime towards the end of time: (Daniel 12:9-13) prophecy.
Camping teaches that the "Church age" is over, that Satan now rules in all churches, and that no person remaining in a church at the time of the Rapture can be saved. He distinguishes his ministry from a "church", saying that Family Radio does not have a "membership" or hold "authority".
Camping now teaches that "hell" is synonymous with "death" and the "grave", and that there is no everlasting torment.
Camping now teaches that The Cross was just a demonstration of what had already happened before the foundation of the world.
According to Camping, the number five equals "atonement", the number ten equals "completeness", and the number seventeen equals "heaven".
Christ is said to have hung on the cross on April 1, 33 AD. The time between April 1, 33 AD and April 1, 2011 is 1,978 years.
If 1,978 is multiplied by 365.2422 days (the number of days in a solar year, not to be confused with the lunar year), the result is 722,449. (This, however, is a rounded number; taken precisely, the figure is 722,449.0716)
The time between April 1 and May 21 is 51 days.
51 added to 722,449 is 722,500.
(5 x 10 x 17)2 or (atonement x completeness x heaven)2 also equals 722,5