A terrible storm causes hundreds of dikes to break in Zeeland, resulting in the North Sea flood of 1953. Julia, a single mother living with her parents, is caught in the middle of the catastrophic flood. She is rescued from drowning and taken to safety by her neighbour Aldo, who is a member of the armed forces. However, her baby is left in a wooden box in the attic of Julia's parental home. Together Julia and Aldo return to the disaster area to look for the baby. When they finally find the box, it is empty, and they conclude that someone must have taken the child. The child ended up with a woman who recently lost her own baby in a car accident. Julia met her but because the woman did not want to lose the baby, she hid him for Julia. Eighteen years later, Julia meets her son and the woman again and she finds out what has happened.
Set in the rural Pacific Northwest, a mysterious character named Silas Hendershot (Luke Perry) takes refuge from a severe thunderstorm in a farm owned by Tom (Steve Bacic) and Gillian Grady (Lauren Holly). He claims that he should stay and that they should watch after each other. Tom starts to dislike Silas and becomes suspicious of him and his past.
1985. Sur sa route, le brise-glace « Mikhaïl Gromov » doit affronter un énorme et puissant iceberg. Voulant éviter une collision fatale, le navire est pris dans les glaces et doit entamer une dérive forcée au large de l'Antarctique. L'équipage est à cran : un froid terrible règne tandis que le carburant touche à sa fin. Il leur est impossible de quitter le brise-glace sous peine de mourir de froid ou de se perdre. Le commandant du brise-glace n'a pas le droit à l'erreur. La moindre mauvaise décision peut les mener à la mort en se faisant écraser par les lourdes glaces.
Andy Goodman (Brian Dennehy) is a week away from a forced retirement from his position as chief meteorologist at the National Weather Administration's Severe Weather Center. However, tornadoes level Las Vegas, an area normally not prone to the storms. Concerned and upset that the storm system formed unnoticed and that they were unable to warn the people, Goodman begins closely tracking the system. Goodman receives field reports from his friend "Tornado Tommy" (Randy Quaid) and assistance from new intern Sabrina Rogers (Alicia Johnston). As time passes, he realizes the system is heading towards Chicago, joined by an unusual warm storm coming from the south, which is already causing a record-breaking heat wave in the city, and an abnormally early cold front from the Arctic.
Following the events in Category 6: Day of Destruction, the superstorm that hit Chicago is continuing to grow in size and strength, with tornadoes hitting Paris and destroying the Eiffel Tower. Judith Carr (Gina Gershon), the new head of FEMA struggles to coordinate efforts to prepare for the aftermath of the storm and provide aid to ravaged areas. She calls in her former college lover, Dr. Ross Duffy (Cameron Daddo), and her father Senator Ryan Carr (Robert Wagner) to help her try to determine what is causing the storms and how to deal with the political issues. Tommy Tornado (Randy Quaid), who survived his seeming death in the previous film, returns to aid in tracking the storm in the United States, assisted by scientist Faith Clavell (Shannen Doherty). Similar storms are developing around the country and an interaction between urban heat islands and "falling chunks of mesosphere" fuels the storms making them more powerful. Hurricane Eduardo strikes toward Florida while the Category 6 storm hits Buffalo and heads towards New York City.