Pushing the envelope. Sometimes this just works. TPA-JFK lands at 8:31AM,at gate 15, connect with Chicago, which pushes off gate 2 at 8:48. Whew.... Return flight cancelled due to weather in Chicago, wait two days for flight loads to allow Non-Rev travel. Land in JFK, gate 5 at 12:45, push off gate 2 to Tampa at 1:20. It's all about the numbers and weather. No-one can call the odds if a flight is going to be on time or not. If it's a huge issue, leave yourself enough time. Happy Holidays!!