The definition’s example from answers.com explains my situation:
Bummer: Slang. One that depresses, frustrates, or disappoints: Getting stranded at the airport was a real bummer.
I was so happy to finish my meetings early. I got on the standby list for the earlier flight. The UA service representative was about to hand me my boarding pass when a red faced person rushed all the way in. Of course that he received his seat. One hour later, after unsuccessfully fighting with ORD’s wireless network, I was on the next flight, just to e deplaned few minutes before takeoff due to an hydraulic problem. Now I’m waiting for a new, unscheduled flight that will bring me home past the arrival time of my original flight.
Yes, the weather in Chicago suck as well.