When Tommy and Faith are in Manhattan, they have to abandon their truck to escape a tidal surge. As they are setting up the last rocket, they look down from the balcony to see the street below them, where they left their truck, the street below them has become a raging river. A few scenes later, Tommy and Faith are seen driving to Washington, D.C. in the same truck.
When their ground crew is 30 miles south of Detroit, they confirm that their coordinates are 42.87 North, 78.86 West. Those coordinates are actually for Buffalo New York, which is the next destination for the tornado. The specific location is 272 Miami Street in Buffalo.
The only view of Chicago was the top parts of the Sears Tower, which looks untouched by a tornado storm. In the last movie (a week earlier), the top of the Sears Tower, at the end of the movie, was very badly damaged.
A TV news report tells of the Mall of America in Minneapolis being destroyed by a major storm, but they were showing the shopping mall, with the ceiling windows caving in, in the previous movie which takes place in Chicago.
Anyone attempting to fly an SR-71 as though it were a fighter (as portrayed in the show's special effects) would be in for a severe surprise, especially in the vicinity of Mach 3. The SR-71 is not an aircraft which tolerates being maneuvered violently. Compressor stalls owing to sudden airflow changes into the engines as well as a general loss of aircraft control would be the least of the pilot's problems! Also, a clear canopy, such as shown in the close-ups would never survive the heat of Mach 3 flight.
SR-71 flight crew do not wear open-faced helmets. In fact, their outfits closely resemble space suits. Besides, if a rapid response to sudden developments is called for, it is definitely not the platform of choice despite its speed, considering the time it takes to preflight the highly complex aircraft and mount a mission. For example, missions always involve at least one in-flight refueling procedure.
During television coverage of Hurricane Eduardo, the reporter states the storm is a Category 5 hurricane with "wind gusts to 150 MPH". 150 MPH winds would actually be classified as Category 4 on the Saffir-Simpson hurricane scale. Further on this, 150 gusts would likely indicate 135 MPH sustained winds, which is still Category 4 (131-155 MPH). Category 5 wind speeds start at 156 MPH sustained with higher gusts.
If you've seen Category 6: Day Of Destruction, you'll notice that almost half of the disaster scenes that was on the news on the TV are taken from the scenes in that part of the series and put into this half (Category 7) of the series. Also, various videos of actual tornadoes and floods are put into this movie.
In Category 7, it is reveled that when the thermal plume from the city collides with a chunk of falling mesosphere, the storms happen. This can be stopped and cause the storms to end if the electricity is gone. But in the first movie, 'Category 6: Day of Destruction' (2004)(TV), Chicago didn't have electricity when the storms hit.
The satellite image of the hurricane as it is hitting DC is clearly an image of another hurricane. It is shown making landfall on the gulf coast, and the outlines of the states clearly show DC (and Virginia and Maryland) having a sunny day (also there is no evidence of the second storm "colliding" with the hurricane).
During the "fight scene" on the street sidewalk between Peter and Stuart with the police officer attempting to break it up one of the three characters "accidentally" expels gas out loud during the fight scene breakup - it was all caught on camera but not removed.