Plot hole: The sergeant tells Stone that he only has to listen for a bell for an important communication coming through and will then alert the rest of Wildfire. Yet later, Dutton notices a message already printed out. So at a facility this important, the sergeant just ignores the machine if it prints out a message and doesn't ring? He has to have clearance to read them or they wouldn't print out where he is. It's a bit too convenient for the plot that he wouldn't visually check each message to make sure.
Continuity mistake: On Day 2, when the two officers go into the town's doctor's office, they leave the van with the driver's door way open, beyond 90 degrees, almost 180. The door didn't move to indicate it corrected itself as they went in. When they come out, the door is almost closed. And there has been no indication of a wind other than the helicopter, and that is supposed to be 1000 feet up and not even close to the office.
Trivia: Unknown at the time, two future Star Trek references are made in this film. The director, Robert Wise, would go on to direct Star Trek: The Motion Picture, and at the end of the film when discussing the cloud seeding, a caption on the video monitor reads out "Nimbus 3". This was the name of the planet on which Sybok takes prisoners in Star Trek V: The Final Frontier.
Question: If the Andromeda "Incident" at Piedmont and the facility were top secret, ever wonder what they did with the old man who knew of both? (I'm excluding the baby, since he can't talk or remember).