The length of Gerard Butler's beard varies from scene to scene.
In the early part of the film, the German character, Ute Fassbinder (Alexandra Maria Lara), can be seen with the flag of the Netherlands on the left shoulder of her overall suit. Later on, on her space suit, the correct flag of Germany is put on.
When Sarah is driving the cab with the president inside, the car's headlights are on but in the next scene only the day running lights are on. In the following scene the car's headlights are on again.
During the phone call at 43:57 Max Lawson and Cheng Long's phone screens are off. In the next shot, they are on.
The shuttle banks into a landing on the flight deck like a fighter, ignoring how objectors actually maneuver in space. On landing in the massive landing deck which is open to space, the doors close and in seconds there is full air pressure and its warm enough to walk out without protective clothing. As the characters greet each other in the background another shuttle departs (using its main engines!) without any apparent effect on the air pressure.
During shuttle flight to the space station, Jake Lawson leaves his seat while engines are still working, and the shuttle has zero gravity inside. According to the laws of physics, zero gravity is possible only if forces acting on shuttle are the same as those working on human body. Working engines cause force acting on shuttle. Zero gravity appears only when engines are off.
The character Cheng Long is shown driving away with the car still plugged-in to a charging station. As a safety feature built-in to every electric-car, it is impossible to drive the car with the plug still attached, nor can the feature be overridden even in an emergency.
The weather control web is presented as a spherical mesh surrounding the earth, with the space station, also in orbit, just above it, with little if any difference in orbital velocity. That part of the mesh, probably its equatorial region, would correctly remain in orbit. The mesh's rotational speed could be offset slightly from orbital speed and the difference in forces could be compensated for by the structural strength of the mesh. However, no matter how fast the mesh was spun, its spin poles would not be held at altitude by any centripetal force and would have to be supported above the earth only by the structural rigidity of the rest of the mesh. This is far, far beyond the strengths of any materials we know of.
At the beginning of the film when the UN soldiers show up at the Afghanistan village that has been frozen, they walk about in what seems to be very comfortable temperatures and you don't even see anyone's breath in the "cold". In fact, when one soldier touches a frozen individual his hand breaks off due to it being, supposedly, so frozen it is brittle. If the temperature was still so cold that they bodies were still frozen to the point of being brittle then they soldiers walking about would at least be showing some effects as well.
In the initial sequence, the satellites are shown as modifying and controlling the weather by sending some sorts of missiles and requiring the presence of the main satellite base to provide them with more ammunition. Yet when the geostorm episode starts all satellite suddenly appear to influence the weather using beams and energy waves of some sort, not projectiles anymore, and therefore being able to influence the weather without anyone involved.
When the people of the security service are chasing the taxi carrying the president, after the bridge collapses and their car comes out of the thick dust, not even a speck of dirt can be seen on the car, even with the high speed of the car. It does not seem logical and possible that there is no dust on the car, and this reveals the use of special effects for this scene.
When Max tells Sarah "This is bigger than you and me.", Dana snarkily corrects him "you and I". The correct grammar is in fact "you and me".
When Jake's daughter heads to the car to take her back to Atlanta, she is replaced with a stand in when walking away from Jake. It's a different and much older girl.
Quite often, when Gerard Butler speaks, the American accent he's using slips, and his true Scottish accent comes through.
Each simple lightning has an energy of about seven gigajoules, which is very destructive, and its contact with surfaces can cause destruction or severe burns. In the scene where the lightning strikes the security officer's car and destroys it (of course with the help of the gasoline in the car), the lightning strikes around the car do not leave even the slightest burn or damage.
When Gerard Butler recovers the hard drive from the space station door, the hard drive reads, 20A with a warning label covered by his fingers . The scene jumps to Ute and right back. The drive has different numbers and different UPC codes. At that point the movie shows no indication of him putting it down and picking it back up. Hard drives also do not have a size or speed designation with the letter "A".
When the taxi comes to pick up Jake Lawson's daughter early in the film, he lazily and unrealistically parks about 40 meters from the gate, even there was no reason that he couldn't have done what Max did and drive right in and through the gate to save his customer from an unnecessary walk.
When Sarah and Max take the president to safety, they drive in between the two secret service agents. The close up view of one of the agents falling clearly shows him falling onto a safety mat and not the concrete he is supposed to be falling onto.
When Max is watching a news report on the Rio de Janeiro storm, the map shown on screen puts Rio de Janeiro almost outside of Brazil to the south. It should be to the northeast of the larger concentration of lights (city of São Paulo).
Just after Cheng Long is hit by the car Secret Service Agent Sarah Wilson follows a vehicle down a street with the dome of The United States Capital clearly shown in the background. There are no streets off of Dupont Circle that would show The Capital building in the line of sight. The closest point would possibly be along Pennsylvanian Avenue via Washington Circle Park which is .6 miles away and that would still require looking through The White House and Executive Building Complex.
The Peter the Great Statue is nowhere near the high-rise shown in the movie.
Gerald Butlers character was the head of the international team that built the entire system and spent a huge amount of time on the space station, yet only a couple of years after being fired walks into a meeting on that station and none of the people working there recognise him? He'd be world famous.
Early on when the computer virus started the countdown to initiate all satellites to fire, which would cause the potential "Geostorm" event, didn't anyone think to just power down the entire system? That's basically what Gerard Butler did when he rebooted it much later with seconds left.
When Max is asking Sarah to break into White House files, Max says "this is bigger than you and me" and Dana corrects him saying "you and I" he was actually correct initially and she was wrong to correct him.
Hannah in her narration says that the satellite system was called Dutch boy after the boy who put his finger in a dam. In the novel 'Hans Brinker, or the Silver Skates' by Mary Mapes Dodge, the boy puts his finger in a dike to stop the ocean. A dam is across a river.