How Do Planes Navigate in the Sky?

The Southwest Airlines blog takes a look at how planes navigate in the sky.

Definitely explains why the delays pile up on the east coast of the United States. Doesn't explain why I have never flown out of O'Hare Airport in Chicago without being delayed.

Ironically, everytime I've flown Southwest Airlines from Chicago (Midway Airport is the only airport in Chicago Southwest uses) the flight has been on time. Everytime I've flown from O'Hare Airport on another airline my flight has been delayed or cancelled.

I'm flying Southwest again from Chicago Midway in September. Will my streak of luck continue?