From one of my favorite sites, Netted.net:
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The site uses a combination of 10 years of flight data and forecasting from the airline, the FAA and current local weather conditions to gauge the likelihood of your flight being delayed or canceled as far as six hours in advance.
It isn’t accurate 100% of the time, but it certainly does not disappoint with an average 95% accuracy rate. The advance warning is also available as a mobile app, allowing much needed spare time for backpack repacking or new flight scheduling.
Even if you do return home to find that a large, bearded, sword-wielding man named Sven has claimed your house, FlightCaster could quickly become your saving grace in a world of delayed flights.
BTW, I’ve heard from a number of people who have had bad experiences with International Speakers Network (ISN). Before signing up for their for-pay Speakers Bureau and “marketing” company, check out: http://burnedbyisn.blogspot.com/ and http://burnedbyisn.blogspot.com/2008/08/what-we-who-have-been-scammed-can-do-to.html, and http://www.ripoffreport.com/advertising-deceptive/international-speake/international-speakers-bureau-ee92c.htm