Here are some pictures and flight paths of past flights. As you will see sometimes the predictions are not right but they do give us a general direction where they will go. Flight predictions are provided by Amateur Radio Altitude Ballooning. To see what a NOAA Ozonesonde payload looks like click here.
UPDATE:
I do not upload every flight anymore. I will just upload the ones I/we go and recover. You can still track them live here Saturdays at 1:00pm central time.
As of March 2018 flights have been rescheduled to 1 per month due to funding cuts. They are activity searching for funding to continue the research.